U.S. patent application number 16/760139 was filed with the patent office on 2020-09-10 for method for producing chemically treated alloy material, and chemical treatment solution regeneration apparatus used in method fo.
The applicant listed for this patent is NIPPON STEEL CORPORATION. Invention is credited to Sayuri IWATA, Keishi MATSUMOTO, Makoto MIYAJIMA, Takamitsu TAKAGI, Akira TSUTO.
Application Number | 20200283907 16/760139 |
Document ID | / |
Family ID | 1000004900085 |
Filed Date | 2020-09-10 |
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United States Patent
Application |
20200283907 |
Kind Code |
A1 |
TAKAGI; Takamitsu ; et
al. |
September 10, 2020 |
METHOD FOR PRODUCING CHEMICALLY TREATED ALLOY MATERIAL, AND
CHEMICAL TREATMENT SOLUTION REGENERATION APPARATUS USED IN METHOD
FOR PRODUCING CHEMICALLY TREATED ALLOY MATERIAL
Abstract
A method for producing a chemically treated alloy material is
provided that suppresses a decrease in chemical treatability even
in a case where chemical treatment is repeatedly performed. The
method for producing a chemically treated alloy material of the
present disclosure includes a chemical treatment step and a
treatment solution regeneration step. In the chemical treatment
step, an alloy material (6) is immersed in an oxalate treatment
solution (4) containing oxalate ions and fluorine ions to perform a
chemical treatment. In the treatment solution regeneration step,
light is radiated to the oxalate treatment solution (4) during the
chemical treatment and/or the oxalate treatment solution (4) after
the chemical treatment.
Inventors: |
TAKAGI; Takamitsu;
(Chiyoda-ku, Tokyo, JP) ; MIYAJIMA; Makoto;
(Chiyoda-ku, Tokyo, JP) ; MATSUMOTO; Keishi;
(Chiyoda-ku, Tokyo, JP) ; IWATA; Sayuri;
(Chiyoda-ku, Tokyo, JP) ; TSUTO; Akira;
(Chiyoda-ku, Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NIPPON STEEL CORPORATION |
Tokyo |
|
JP |
|
|
Family ID: |
1000004900085 |
Appl. No.: |
16/760139 |
Filed: |
November 21, 2018 |
PCT Filed: |
November 21, 2018 |
PCT NO: |
PCT/JP2018/043073 |
371 Date: |
April 29, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C23C 22/34 20130101;
C23C 22/86 20130101; C23C 22/46 20130101 |
International
Class: |
C23C 22/46 20060101
C23C022/46; C23C 22/34 20060101 C23C022/34; C23C 22/86 20060101
C23C022/86 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 24, 2017 |
JP |
2017-226309 |
Apr 11, 2018 |
JP |
2018-076359 |
Claims
1. A method for producing a chemically treated alloy material,
comprising: a chemical treatment step of immersing an alloy
material in an oxalate treatment solution containing oxalate ions
and fluorine ions to perform chemical treatment of the alloy
material; and a treatment solution regeneration step of radiating
light at the oxalate treatment solution during the chemical
treatment and/or the oxalate treatment solution after the chemical
treatment.
2. The method for producing a chemically treated alloy material
according to claim 1, wherein: in the treatment solution
regeneration step, light is radiated to the oxalate treatment
solution while causing the oxalate treatment solution to flow.
3. The method for producing a chemically treated alloy material
according to claim 1, wherein: in the treatment solution
regeneration step, wavelengths of the light include a wavelength in
an ultraviolet range.
4. The method for producing a chemically treated alloy material
according to claim 1, further comprising: a step of adding oxalate
ions to the oxalate treatment solution.
5. The method for producing a chemically treated alloy material
according to claim 1, wherein: the oxalate treatment solution
further contains nitrate ions.
6. The method for producing a chemically treated alloy material
according to claim 1, wherein: the oxalate treatment solution
further contains thiosulfate ions.
7. The method for producing a chemically treated alloy material
according to claim 1, wherein: the alloy material contains 10.5% or
more of Cr.
8. A chemical treatment solution regeneration apparatus,
comprising: a treatment solution regeneration bath capable of
containing an oxalate treatment solution that contains oxalate ions
and fluorine ions, during chemical treatment or after the chemical
treatment of an alloy material; and a light radiation apparatus
that includes one or more light source members, with at least one
part of the light source member being disposed inside the treatment
solution regeneration bath or in a vicinity of an outer side of the
treatment solution regeneration bath, the light radiation apparatus
being capable of radiating light at the oxalate treatment solution
during the chemical treatment or after the chemical treatment.
9. The chemical treatment solution regeneration apparatus according
to claim 8, wherein: at least one part of the light source member
is immersible in the oxalate treatment solution in the treatment
solution regeneration bath.
10. The chemical treatment solution regeneration apparatus
according to claim 8, further comprising: a flow mechanism that
causes the oxalate treatment solution in the treatment solution
regeneration bath to flow.
11. The chemical treatment solution regeneration apparatus
according to claim 10, further comprising: a chemical treatment
bath capable of containing the oxalate treatment solution after
being irradiated with the light by the light radiation apparatus in
the treatment solution regeneration bath, the chemical treatment
bath allowing the chemical treatment to be performed by immersing
the alloy material in the oxalate treatment solution that is
contained in the chemical treatment bath; wherein the flow
mechanism comprises: a first liquid supply channel that conveys the
oxalate treatment solution in the treatment solution regeneration
bath to the chemical treatment bath, and a second liquid supply
channel that conveys the oxalate treatment solution in the chemical
treatment bath to the treatment solution regeneration bath.
12. The chemical treatment solution regeneration apparatus
according to claim 11, wherein: the chemical treatment bath
includes: a first chemical treatment bath and a second chemical
treatment bath; the first liquid supply channel including: a first
liquid supply channel main body having two end portions on the
chemical treatment bath side, a first chemical-treatment-bath-side
discharge port that is formed at one of the end portions on the
chemical treatment bath side of the first liquid supply channel
main body and that discharges the oxalate treatment solution in the
first liquid supply channel main body into the first chemical
treatment bath, and a second chemical-treatment-bath-side discharge
port that is formed at the other of the end portions on the
chemical treatment bath side of the first liquid supply channel
main body and that discharges the oxalate treatment solution in the
first liquid supply channel main body into the second chemical
treatment bath; the second liquid supply channel including: a
second liquid supply channel main body having two end portions on
the chemical treatment bath side, a first
chemical-treatment-bath-side inflow port that is formed at one of
the end portions on the chemical treatment bath side of the second
liquid supply channel main body and that allows the oxalate
treatment solution in the first chemical treatment bath to flow
into the second liquid supply channel main body, and a second
chemical-treatment-bath-side inflow port that is formed at the
other of the end portions on the chemical treatment bath side of
the second liquid supply channel main body and that allows the
oxalate treatment solution in the second chemical treatment bath to
flow into the second liquid supply channel; and the flow mechanism
further comprises: a discharge port switching mechanism that
switches whether to cause the oxalate treatment solution in the
first liquid supply channel main body to be discharged from the
first chemical-treatment-bath-side discharge port or from the
second chemical-treatment-bath-side discharge port, and an inflow
port switching mechanism that switches whether to cause the oxalate
treatment solution to flow into the second liquid supply channel
main body from the first chemical-treatment-bath-side inflow port
or from the second chemical-treatment-bath-side inflow port.
13. The chemical treatment solution regeneration apparatus
according to claim 10, wherein: the flow mechanism comprises: an
under-regeneration-treatment-solution circulation channel that
causes the oxalate treatment solution in the treatment solution
regeneration bath to circulate; the
under-regeneration-treatment-solution circulation channel
comprises: an under-regeneration-treatment-solution circulation
channel main body having two end portions, the
under-regeneration-treatment-solution circulation channel main body
being capable of containing one part of the oxalate treatment
solution in the treatment solution regeneration bath, an
under-regeneration-treatment-solution inflow port that is formed at
one of the end portions of the
under-regeneration-treatment-solution circulation channel main
body, and that allows the oxalate treatment solution in the
treatment solution regeneration bath to flow into the
under-regeneration-treatment-solution circulation channel main
body, an under-regeneration-treatment-solution discharge port that
is formed at the other end portion of the
under-regeneration-treatment-solution circulation channel main
body, and that discharges the oxalate treatment solution in the
under-regeneration-treatment-solution circulation channel main body
into the treatment solution regeneration bath, and an
under-regeneration-treatment-solution circulation driving source
that causes the oxalate treatment solution in the
under-regeneration-treatment-solution circulation channel main body
to move from the under-regeneration-treatment-solution inflow port
to the under-regeneration-treatment-solution discharge port; and at
least one of the light source members is disposed between the
under-regeneration-treatment-solution inflow port and the
under-regeneration-treatment-solution discharge port.
14. The chemical treatment solution regeneration apparatus
according to claim 8, wherein: at least one part of a bottom face
of the treatment solution regeneration bath is inclined.
15. The chemical treatment solution regeneration apparatus
according to claim 8, wherein: the treatment solution regeneration
bath is partitioned into a light irradiation chamber and a
sedimentation chamber by a partition member; the partition member
has an opening portion that connects the light irradiation chamber
and the sedimentation chamber; and the one or more light source
members are disposed in the light irradiation chamber.
16. The chemical treatment solution regeneration apparatus
according to claim 15, wherein: a bottom face of the light
irradiation chamber becomes lower in a direction from the light
irradiation chamber toward the sedimentation chamber.
17. The chemical treatment solution regeneration apparatus
according to claim 10, wherein: the treatment solution regeneration
bath further comprises a current direction changing member that is
disposed so as to be immersible in the oxalate treatment solution
in the treatment solution regeneration bath and that changes a
direction of a flow of the oxalate treatment solution in the
treatment solution regeneration bath.
18. The chemical treatment solution regeneration apparatus
according to claim 8, wherein: the light radiation apparatus is an
ultraviolet radiation apparatus.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a method for producing a
chemically treated alloy material, and a chemical treatment
solution regeneration apparatus that is used in the method for
producing a chemically treated alloy material.
BACKGROUND ART
[0002] The surface of an alloy material is subjected to chemical
treatment for the purpose of imparting performance such as
corrosion resistance, galling resistance, lubricity and paint
adhesiveness to the alloy material. Examples of the chemical
treatments include a phosphate treatment, an oxalate treatment and
a chromate treatment. Among such chemical treatments, an oxalate
treatment is performed for the purpose of increasing the lubricity,
galling resistance and the like of the alloy material surface. An
oxalate coating that is formed on an alloy material surface by an
oxalate treatment increases the adhesiveness to the alloy material
surface of a lubricating film that is to be formed thereon. In this
way, the oxalate coating increases the lubricity and galling
resistance of the alloy material surface.
[0003] For example, Japanese Patent Application Publication No.
2006-37933 (Patent Literature 1) discloses a technique that
provides a high chromium steel piston that has excellent galling
resistance by forming an oxalate coating on the surface of a piston
for use in an internal combustion engine.
[0004] An oxalate treatment is usually performed by immersing an
alloy material in an oxalate treatment solution containing oxalate
ions, and causing a reacting between the alloy material surface and
the oxalate treatment solution. In the case of performing an
oxalate treatment on a plurality of alloy materials, usually the
oxalate treatment solution is used continuously. The chemical
treatability decreases as the number of alloy materials that are
successively treated increases. If the chemical treatability
decrease, in some cases defects occur in the formation of the
oxalate coating. Further, it is known that, in a case where the
alloy material contains a large amount of Cr, that is, is a
so-called "difficult-to-chemically-treat material", even when the
usage count of the oxalate treatment solution is low, the chemical
treatability decrease. In such a case, defects may occur in the
formation of an oxalate coating. Therefore, various studies have
been conducted regarding techniques for suppressing a decrease in
the chemical treatability.
[0005] Japanese Patent Application Publication No. 2003-171777
(Patent Literature 2), Japanese Patent Application Publication No.
2-149677 (Patent Literature 3) and Japanese Patent Application
Publication No. 2014-43606 (Patent Literature 4) propose oxalate
treatment solutions that can suppress a decrease in chemical
treatability. On the other hand, Japanese Patent Application
Publication No. 62-199778 (Patent Literature 5) and Japanese Patent
Application Publication No. 6-220651 (Patent Literature 6) propose
chemical treatment methods that can suppress a decrease in chemical
treatability.
[0006] A treatment solution for forming an oxalate coating
disclosed in Patent Literature 2 is characterized by containing a
polyoxyethylene-polyoxypropylene block copolymer in an amount of
0.03 to 1.0 wt % that is obtained by adding ethylene oxide of 20 to
50 wt % with respect to the total molecular weight to propylene
glycol. It is described in Patent Literature 2 that by this means,
in a method that performs cold drawing of stainless pipes, a
reduction in the defect rate of products as well as suppression of
a decrease in the life time of the oxalate coating treatment
solution are achieved.
[0007] A chemical treatment solution for cold working of stainless
steel disclosed in Patent Literature 3 contains oxalic acid, and is
characterized in that phosphoric acid is contained in an amount
such that a phosphate ion concentration in the treatment solution
falls within a range of 0.03 to 0.6 g/L. It is described in Patent
Literature 3 that by this means, even though the balance of the
composition of the chemical treatment solution becomes unbalanced
to a certain extent, a chemical treatment solution is obtained that
can form, on the surface of stainless steel, a chemical coating
which can maintain favorable galling resistance.
[0008] An oxalate chemical treatment method disclosed in Patent
Literature 4 is characterized by adding sulfite as an accelerating
agent to an oxalate chemical treatment solution to perform a
chemical treatment. It is described in Patent Literature 4 that by
this means an oxalate coating can be formed on a material which has
high corrosion resistance, such as a high corrosion-resistant
stainless pipe.
[0009] A method for forming an oxalate coating on Cr--Ni stainless
steel disclosed in Patent Literature 5 is characterized by
performing a sulfuric acid treatment immediately before an oxalate
coating forming treatment. It is described in Patent Literature 5
that by this means the reactivity between the starting material and
the oxalate treatment solution increases, and oxalate coating
forming treatment can be performed efficiently even with respect to
high Ni steel for which it had conventionally not been possible to
perform an oxalate coating forming treatment on.
[0010] A method for performing lubrication treatment of a highly
corrosion resistant metal material disclosed in Patent Literature 6
is characterized by forming an oxalate coating without performing a
pickling treatment after performing a shot blasting treatment with
iron and steel shot on the surface of a metal material, and
subsequently performing a lubrication treatment. It is described in
Patent Literature 6 that by this means, even in the case of a metal
material with high corrosion resistance on which it is difficult to
perform a chemical treatment, a chemical coating can be
sufficiently formed, and an appropriate lubrication treatment can
be performed.
CITATION LIST
Patent Literature
[0011] Patent Literature 1: Japanese Patent Application Publication
No. 2006-37933
[0012] Patent Literature 2: Japanese Patent Application Publication
No. 2003-171777
[0013] Patent Literature 3: Japanese Patent Application Publication
No. 2-149677
[0014] Patent Literature 4: Japanese Patent Application Publication
No. 2014-43606
[0015] Patent Literature 5: Japanese Patent Application Publication
No. 62-199778
[0016] Patent Literature 6: Japanese Patent Application Publication
No. 6-220651
SUMMARY OF INVENTION
Technical Problem
[0017] When the techniques described above are used, a decrease in
chemical treatability can be suppressed. On the other hand, it
would also be good if a decrease in chemical treatability can be
suppressed by another method other than the techniques described
above.
[0018] An objective of the present disclosure is to provide a
method for producing a chemically treated alloy material which
suppresses a decrease in chemical treatability even in a case where
chemical treatment is repeatedly performed, and a chemical
treatment solution regeneration apparatus that can suppress a
decrease in the chemical treatability of an alloy material even in
a case of producing a chemically treated alloy material using an
oxalate treatment solution with which chemical treatment is
repeatedly performed.
Solution to Problem
[0019] The method for producing a chemically treated alloy material
of the present disclosure includes a chemical treatment step and a
treatment solution regeneration step. In the chemical treatment
step, an alloy material is immersed in an oxalate treatment
solution containing oxalate ions and fluorine ions to perform a
chemical treatment. In the treatment solution regeneration step,
light is radiated to the oxalate treatment solution during the
chemical treatment and/or the oxalate treatment solution after the
chemical treatment.
[0020] The chemical treatment solution regeneration apparatus of
the present disclosure includes a treatment solution regeneration
bath and a light radiation apparatus. The treatment solution
regeneration bath is capable of containing an oxalate treatment
solution during chemical treatment of an alloy material or after
the chemical treatment of an alloy material. The oxalate treatment
solution contains oxalate ions and fluorine ions. The light
radiation apparatus includes one or more light source members. At
least one part of the light source member is disposed inside the
treatment solution regeneration bath or in the vicinity of an outer
side of the treatment solution regeneration bath. The light
radiation apparatus is capable of radiating light at the oxalate
treatment solution during the chemical treatment or after the
chemical treatment.
Advantageous Effects of Invention
[0021] According to the method for producing a chemically treated
alloy material of the present disclosure, a decrease in chemical
treatability is suppressed even in a case where chemical treatment
is repeatedly performed. The chemical treatment solution
regeneration apparatus of the present disclosure can suppress a
decrease in the chemical treatability of an alloy material even in
the case of producing a chemically treated alloy material using an
oxalate treatment solution with which chemical treatment is
repeatedly performed.
BRIEF DESCRIPTION OF DRAWINGS
[0022] FIG. 1 is a view showing the content of trivalent iron ions
of an oxalate treatment solution after use for chemical treatment
of an alloy material, before and after ultraviolet irradiation.
[0023] FIG. 2 is a view showing the potential on the surface of an
alloy material in cases where the alloy material was subjected to
chemical treatment using an unused oxalate treatment solution, a
used oxalate treatment solution, and a regenerated treatment
solution.
[0024] FIG. 3 is a schematic diagram of one example of a chemical
treatment solution regeneration apparatus that is used in a method
for producing a chemically treated alloy material according to the
present embodiment.
[0025] FIG. 4 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3.
[0026] FIG. 5 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 and FIG. 4.
[0027] FIG. 6 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 5.
[0028] FIG. 7 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 6.
[0029] FIG. 8 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 7.
[0030] FIG. 9 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 8.
[0031] FIG. 10 is a schematic diagram illustrating an example of a
treatment solution regeneration bath in which the bottom face is
inclined.
[0032] FIG. 11 is a schematic diagram illustrating an example of a
treatment solution regeneration bath that is different from FIG.
10.
[0033] FIG. 12 is a schematic diagram illustrating an example of a
treatment solution regeneration bath that is different from FIG. 10
and FIG. 11.
[0034] FIG. 13 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 12.
[0035] FIG. 14 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 13.
[0036] FIG. 15 is a plan view of a treatment solution regeneration
bath illustrating the arrangement of current direction changing
members.
[0037] FIG. 16 is a plan view of a treatment solution regeneration
bath illustrating the arrangement of current direction changing
members that is different from FIG. 15.
[0038] FIG. 17 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 16.
[0039] FIG. 18 is a schematic diagram illustrating an example of
the arrangement of light source members.
[0040] FIG. 19 is a schematic diagram illustrating an example of
the arrangement of light source members that is different from FIG.
18.
[0041] FIG. 20 is a schematic diagram illustrating an example of
the arrangement of light source members that is different from FIG.
18 and FIG. 19.
[0042] FIG. 21 is a schematic diagram illustrating an example of
the arrangement of light source members that is different from FIG.
18 to FIG. 20.
[0043] FIG. 22 is a schematic diagram illustrating an example of
the shape of a treatment solution regeneration bath.
[0044] FIG. 23 is a schematic diagram illustrating an example of
the shape of a treatment solution regeneration bath that is
different from FIG. 22.
[0045] FIG. 24 is a schematic diagram illustrating an example of
the shape of a treatment solution regeneration bath that is
different from FIG. 22 and FIG. 23.
[0046] FIG. 25 is a schematic diagram illustrating an example of
the shape of a treatment solution regeneration bath that is
different from FIG. 22 to FIG. 24.
[0047] FIG. 26 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 25.
[0048] FIG. 27 is a schematic diagram of a chemical treatment
solution regeneration apparatus according to another embodiment
that is different from FIG. 3 to FIG. 26.
DESCRIPTION OF EMBODIMENTS
[0049] An oxalate coating is a coating that is consisting of iron
(II) oxalate (chemical formula: Fe(COO).sub.2) and impurities. An
oxalate coating is formed as the result of iron ions that are
eluted from an alloy material and oxalate ions contained in an
oxalate treatment solution reacting at the alloy material surface.
The formation process of iron (II) oxalate in a chemical treatment
is, specifically, shown by the following reaction formulae.
Fe.fwdarw.Fe.sup.2++2e.sup.- (1)
(COOH).sub.2.fwdarw.(COO).sub.2.sup.2-+2H.sup.+ (2)
2H.sup.++2e.sup.-.fwdarw.H.sub.2.uparw. (3)
(COO).sub.2.sup.2-+Fe.sup.2+.fwdarw.Fe(COO).sub.2 (4)
[0050] Fluorine ions are added into the oxalate treatment solution
to accelerate the above reactions. Fluorine ions have an etching
action. If fluorine ions are contained in an oxalate treatment
solution for chemical treatment, the fluorine ions destroy an oxide
film (passivation film) that is formed on the surface of the base
metal surface in the process of producing an alloy material. As a
result, formation of an oxalate coating is promoted. In addition,
an oxalate coating can also be formed on a stainless alloy material
having a passivation film with high corrosion resistance.
[0051] It is already known that an oxalate treatment solution
containing oxalate ions and fluorine ions deteriorates due to
repetitive use of the oxalate treatment solution. If the oxalate
treatment solution deteriorates, the chemical treatability may
decrease. If the chemical treatability decrease, in some cases
defects may occur in the formation of an oxalate coating. Further,
it is known that, in a case where the alloy material contains a
large amount of Cr, that is, the alloy material is a so-called
"difficult-to-chemically-treat material", even when the usage count
of the oxalate treatment solution is low, the chemical treatability
are low.
[0052] Conventionally, these problems have been dealt with by
adding an etching agent such as sodium bifluoride into the oxalate
treatment solution or by raising the treatment temperature.
Further, in a case where the problems could not be dealt with by
the above methods, the entire oxalate treatment solution is
discarded and replaced. In the case of treating a
difficult-to-chemically-treat material, measures such as imparting
surface roughness to the alloy material surface or imparting iron
content to the alloy material surface have been adopted. On the
other hand, detailed studies had heretofore not been conducted with
regard to the cause of a deterioration in an oxalate treatment
solution and the cause of defects in the formation of an oxalate
coating.
[0053] Therefore, the present inventors conducted a detailed study
regarding the cause of a deterioration in an oxalate treatment
solution and the cause of a decrease in chemical treatability. As a
result, the present inventors obtained the findings described
hereunder that had not been known before now.
[0054] During chemical treatment, iron from the base metal
dissolves and iron ions are generated. At such time, a part of the
iron of the base metal dissolves as divalent iron ions (Fe.sup.2+),
as shown in the above Formula (1). The divalent iron ions react
with oxalate ions to form iron (II) oxalate. Iron (II) oxalate is
an insoluble salt. Therefore, when iron dissolves as divalent ions
from the alloy material surface and reacts with oxalate ions, iron
(II) oxalate rapidly deposits on the alloy material surface. The
deposited iron (II) oxalate forms an oxalate coating.
[0055] On the other hand, a part of the iron that eluted from the
base metal is present in the oxalate treatment solution as
trivalent iron ions (Fe.sup.3+). The trivalent iron ions do not
contribute to formation of the oxalate coating. That is, it is not
the case that all of the iron ions that eluted from the base metal
are consumed by the formation of an oxalate coating. A part of the
iron ions do not participate in formation of the oxalate coating,
and are present in the oxalate treatment solution.
[0056] The trivalent iron ions react with fluorine ions in the
manner shown in the following Formula (5) to form a complex
(chemical formula: [FeF.sub.6].sup.3-). When a complex is formed,
the etching action disappears, and destruction of the oxide film
(passivation film) is suppressed.
Fe.sup.3++6F.sup.-.fwdarw.[FeF.sub.6].sup.3- (5)
[0057] If an oxalate treatment solution is used repetitively and a
plurality of alloy materials are immersed in the same oxalate
treatment solution, the iron ion content of the oxalate treatment
solution increases. If the iron ion content of the oxalate
treatment solution increases, complex formation between iron ions
and fluorine ions proceeds. That is, if an oxalate treatment
solution is used repetitively, the etching action decreases. As a
result, destruction of the oxide film (passivation film) is
suppressed and the chemical treatability decrease. The present
inventors clarified for the first time that this is the cause of
deterioration in an oxalate treatment solution.
[0058] Further, an alloy material which contains a large amount of
Cr, that is, a so-called "difficult-to-chemically-treat material",
includes a passivation film that has markedly high corrosion
resistance on the surface thereof. Therefore, in the case of
performing an oxalate treatment on a difficult-to-chemically-treat
material, it is necessary to more actively maintain the etching
action of fluorine ions. However, if iron dissolves during the
oxalate treatment and forms a complex with fluorine ions, the
number of fluorine ions may be reduced and the etching action may
decrease, and therefore it may be difficult to destroy the
passivation film. Consequently, defects may occur in the formation
of the oxalate coating.
[0059] As described above, it has been found that the cause of a
decrease in chemical treatability is a decrease in the etching
action of fluorine ions. Therefore, the present inventors studied
methods for restoring and maintaining the etching action of
fluorine ions in an oxalate treatment solution. As a result, the
present inventors obtained the following findings.
[0060] As described above, iron ions in an oxalate treatment
solution react with fluorine ions to form a complex. In this
regard, the present inventors had the idea that if the iron ion
content of an oxalate treatment solution can be reduced, reaction
with fluorine ions (complex formation) can be suppressed. As the
result of various studies, the present inventors obtained the new
finding that the iron ion content of an oxalate treatment solution
can be reduced by the simple method of radiating light at the
oxalate treatment solution.
[0061] FIG. 1 is a view that illustrates the trivalent iron ion
content of an oxalate treatment solution after being used for
chemical treatment of an alloy material (an oxalate treatment
solution after performing a chemical treatment of immersing a
stainless pipe for approximately two hours in a treatment bath that
contained approximately 15000 L of oxalate treatment solution with
respect to a pipe having a total area of approximately 25000
m.sup.2 calculated by surface area conversion) with respect to
before and after ultraviolet irradiation. The ordinate in FIG. 1
represents the trivalent iron ion content (g/L) of the oxalate
treatment solution. The trivalent iron ion content of the oxalate
treatment solution before ultraviolet irradiation is shown on the
left side, and the trivalent iron ion content of the oxalate
treatment solution after ultraviolet irradiation is shown on the
right side in FIG. 1. Referring to FIG. 1, it is found that the
trivalent iron ion content decreases when the used oxalate
treatment solution is subjected to ultraviolet irradiation.
[0062] Next, the present inventors performed a chemical treatment
on an alloy material using an oxalate treatment solution after
ultraviolet irradiation (hereunder, referred to simply as
"regenerated treatment solution"). FIG. 2 is a view illustrating
the potential on an alloy material surface in a case where the
alloy material was subjected to chemical treatment using an unused
oxalate treatment solution (shown as "unused solution" in FIG. 2),
a used oxalate treatment solution (shown as "used solution" in FIG.
2), and an oxalate treatment solution that was a solution obtained
when ultraviolet light was radiated to a used oxalate treatment
solution (shown as "regenerated treatment solution" in FIG. 2). The
abscissa in FIG. 2 represents the reaction time (minutes). The
ordinate in FIG. 2 represents the potential (VvsSCE) on the alloy
material surface. In a case where a dissolution reaction of an
oxide film on the alloy material surface is proceeding, and in a
case where a dissolution reaction of the base metal is proceeding,
the surface potential of the alloy material becomes lower (becomes
base). That is, when a formation reaction of an oxalate coating is
proceeding, a state in which the potential on the alloy material
surface is low (is base) is maintained. In contrast, when a
formation reaction of an oxalate coating is not proceeding, a state
in which the potential on the alloy material surface is high (is
noble) is maintained.
[0063] Referring to FIG. 2, in the case where the unused oxalate
treatment solution (referred to as "unused solution" in FIG. 2) was
used, the potential was high for a very early period of the
reaction. This is because the oxide film on the alloy material
surface was dissolving. However, immediately thereafter the
potential decreases and a low state of about -0.40 V was maintained
for around 200 minutes. On the other hand, in the case where a used
oxalate treatment solution (referred to as "used solution" in FIG.
2) was used, the potential maintained a comparatively high state of
about 0.00 V from the initial state of the reaction until the end
of the test (approximately 200 minutes). In the case where the
oxalate treatment solution after ultraviolet irradiation
(regenerated treatment solution) was used, the potential was
comparatively high for a very early period of the reaction.
However, immediately thereafter the potential decreased, and after
around 20 minutes became the same potential as the potential of the
unused oxalate treatment solution. Thereafter, the low potential
state was maintained until around 200 minutes had passed. Thus, by
radiating ultraviolet light at a used oxalate treatment solution,
the chemical treatability was restored to the same level as the
chemical treatability of an unused oxalate treatment solution, and
hence high chemical treatability were maintained.
[0064] The reason why the chemical treatability of a used oxalate
treatment solution are restored to and maintained at the same level
as the chemical treatability of an unused oxalate treatment
solution by radiating ultraviolet light at the used oxalate
treatment solution is thought to be as follows.
[0065] If the complex formed as shown in Formula (5) is irradiated
with ultraviolet light, trivalent iron ions are reduced to divalent
iron ions as shown in Formula (6). At this time, fluorine ions are
released from the complex. The released fluorine ions regain an
etching action and contribute to destruction of the oxide film
(passivation film). As a result, the chemical treatability of the
used oxalate treatment solution are restored.
[FeF.sub.6].sup.3-+e.sup.-.fwdarw.Fe.sup.2++6F.sup.- (6)
[0066] In addition, the divalent iron ions react with oxalate ions
in accordance with Formula (4) to form insoluble iron (II) oxalate.
At this time, fluorine ions are further released from the complex.
The released fluorine ions regain an etching action. Thus, by
irradiation with ultraviolet light, reduction of trivalent iron
ions followed by formation of insoluble salt occurs, and fluorine
ions are thereby released. Therefore, by irradiation with
ultraviolet light, the chemical treatability of a used oxalate
treatment solution are restored to the same level as the chemical
treatability of an unused oxalate treatment solution.
[0067] On the other hand, trivalent iron ions eluted from the base
metal react with oxalate ions to form iron (III) oxalate (chemical
formula: Fe.sub.2(C.sub.2O.sub.4).sub.3). Iron (III) oxalate has a
property of decomposing to insoluble iron (II) oxalate and carbon
dioxide under light irradiation. By this means, the trivalent iron
ion content of the oxalate treatment solution is decreased. As a
result, reaction between fluorine ions and iron ions is suppressed.
That is, the etching activity of the fluorine ions is maintained,
and high chemical treatability are maintained.
2[Fe(C.sub.2O.sub.4).sub.3].sup.3-.fwdarw.2Fe(COO).sub.2+2CO.sub.2+3(COO-
).sub.2.sup.2- (7)
[0068] Based on these results, the present inventors discovered a
method for producing a chemically treated alloy material that can
maintain the etching action of fluorine ions and suppress a
decrease in chemical treatability by the simple technique of
radiating light. According to the method for producing a chemically
treated alloy material of the present disclosure, it is not
necessarily required to add a component (in particular, an etching
agent such as sodium bifluoride) to an oxalate treatment solution
or to discard and replace an oxalate treatment solution or the
like. Further, even in the case of using a
difficult-to-chemically-treat material, an additional step such as
imparting surface roughness thereto is not necessarily
required.
[0069] In addition, the present inventors concluded that if an
apparatus is equipped with, for example, a treatment solution
regeneration bath capable of containing an oxalate treatment
solution during chemical treatment or after chemical treatment of
an alloy material, and a light radiation apparatus capable of
radiating light at an oxalate treatment solution during chemical
treatment or after chemical treatment, the apparatus can be used in
a method for producing a chemically treated alloy material as
described above.
[0070] A method for producing a chemically treated alloy material
of the present disclosure, which has been completed based on the
above findings, includes a chemical treatment step and a treatment
solution regeneration step. In the chemical treatment step, an
alloy material is immersed in an oxalate treatment solution
containing oxalate ions and fluorine ions to perform a chemical
treatment. In the treatment solution regeneration step, light is
radiated to the oxalate treatment solution during the chemical
treatment and/or the oxalate treatment solution after the chemical
treatment.
[0071] The method for producing a chemically treated alloy material
of the present disclosure includes a treatment solution
regeneration step. By means of the treatment solution regeneration
step, an etching action of fluorine ions is restored, and the iron
ion content of the oxalate treatment solution decreases. If the
iron ions in the oxalate treatment solution are decreased, the
action of fluorine ions of the oxalate treatment solution is more
actively maintained. As a result, even in a case where chemical
treatment is repeatedly performed, a decrease in the chemical
treatability can be suppressed. In the present description, a
coating consisting of iron (II) oxalate and impurities is referred
to as an "oxalate coating". In the present description, an alloy
material that includes an oxalate coating on the surface thereof is
referred to as a "chemically treated alloy material". In the
present description, the meaning of the term "oxalate ions"
includes both oxalate ions (chemical formula:
C.sub.2O.sub.4.sup.2-) and hydrogen oxalate ions (chemical formula:
HC.sub.2O.sub.4).
[0072] Preferably, in the aforementioned treatment solution
regeneration step, light is radiated to the oxalate treatment
solution while causing the oxalate treatment solution to flow.
[0073] In this case, light can be radiated more efficiently at the
oxalate treatment solution.
[0074] Preferably, in the aforementioned treatment solution
regeneration step, wavelengths of the light include a wavelength in
the ultraviolet range.
[0075] In a case where the wavelengths of light that a light source
member emits are short wavelengths of high intensity, a
decomposition reaction of iron (III) oxalate to iron (II) oxalate
is further accelerated. Therefore, a wavelength of the light is
preferably a wavelength in the ultraviolet range. Here, the phrase
"a wavelength in the ultraviolet range" means a wavelength in the
range of 10 to 400 nm.
[0076] Preferably, the method for producing a chemically treated
alloy material further includes a step of adding oxalate ions to
the oxalate treatment solution.
[0077] Oxalate ions are consumed as the iron ion content of the
oxalate treatment solution is reduced. If a step of adding oxalate
ions is included, consumed oxalate ions are replenished. Therefore,
the chemical treatment is accelerated.
[0078] Preferably, the aforementioned oxalate treatment solution
further contains nitrate ions.
[0079] In this case, the chemical treatment is accelerated.
[0080] Preferably, the aforementioned oxalate treatment solution
further contains thiosulfate ions.
[0081] In this case, the chemical treatment is accelerated.
[0082] The aforementioned alloy material may contain 10.5% or more
of Cr.
[0083] According to the method for producing a chemically treated
alloy material of the present disclosure, even in a case of
repeatedly performing a chemical treatment using an alloy material
containing a large amount of Cr, a decrease in the chemical
treatability can be suppressed.
[0084] A chemical treatment solution regeneration apparatus of the
present disclosure is a chemical treatment solution regeneration
apparatus that is used to produce a chemically treated alloy
material. The chemical treatment solution regeneration apparatus
includes a treatment solution regeneration bath and a light
radiation apparatus. The treatment solution regeneration bath is
capable of containing an oxalate treatment solution during chemical
treatment of an alloy material or after the chemical treatment of
an alloy material. The oxalate treatment solution contains oxalate
ions and fluorine ions. The light radiation apparatus includes one
or more light source members. At least one part of the light source
member is disposed inside the treatment solution regeneration bath
or in the vicinity of an outer side of the treatment solution
regeneration bath. The light radiation apparatus is capable of
radiating light at the oxalate treatment solution during the
chemical treatment or after the chemical treatment.
[0085] The chemical treatment solution regeneration apparatus of
the present disclosure includes a light radiation apparatus. The
light radiation apparatus is capable of radiating at the oxalate
treatment solution during the chemical treatment or after the
chemical treatment by means of one or more light source members.
Thus, the oxalate treatment solution can be subjected to a
regeneration treatment. As a result, a decrease in chemical
treatability can be suppressed even in a case where chemical
treatment is repeated.
[0086] Preferably, at least one part of the light source member is
immersible in the oxalate treatment solution in the treatment
solution regeneration bath.
[0087] By immersing at least one part of the light source member in
the oxalate treatment solution in the treatment solution
regeneration bath, the distance between the light source and the
oxalate treatment solution is shortened. Therefore, stronger light
can be radiated to the oxalate treatment solution. As a result, the
oxalate treatment solution can be subjected to regeneration
treatment more efficiently.
[0088] Preferably, the chemical treatment solution regeneration
apparatus includes a flow mechanism that causes the oxalate
treatment solution in the treatment solution regeneration bath to
flow.
[0089] If the oxalate treatment solution in the treatment solution
regeneration bath is caused to flow by the flow mechanism, the
amount of oxalate treatment solution to be irradiated with light
increases. As a result, the oxalate treatment solution can be
subjected to regeneration treatment more efficiently.
[0090] The chemical treatment solution regeneration apparatus may
further include a chemical treatment bath. The chemical treatment
bath is capable of containing the oxalate treatment solution after
the oxalate treatment solution was irradiated with the light by the
light radiation apparatus in the treatment solution regeneration
bath. A chemical treatment can be performed in the chemical
treatment bath by immersing the alloy material in the oxalate
treatment solution contained therein. In a case where the chemical
treatment solution regeneration apparatus includes a chemical
treatment bath, the flow mechanism includes a first liquid supply
channel and a second liquid supply channel. The first liquid supply
channel conveys the oxalate treatment solution in the treatment
solution regeneration bath to the chemical treatment bath. The
second liquid supply channel conveys the oxalate treatment solution
in the chemical treatment bath to the treatment solution
regeneration bath.
[0091] When the chemical treatment solution regeneration apparatus
further includes a chemical treatment bath, the chemical treatment
and the regeneration of the oxalate treatment solution can be
performed in separate baths. By circulating the oxalate treatment
solution between the chemical treatment bath and the treatment
solution regeneration bath by means of the first liquid supply
channel and the second liquid supply channel, even in a case of
performing chemical treatments in succession, a decrease in the
chemical treatability can be continued to be suppressed.
[0092] The chemical treatment bath may include a first chemical
treatment bath and a second chemical treatment bath. In this case,
the first liquid supply channel includes a first liquid supply
channel main body, a first chemical-treatment-bath-side discharge
port and a second chemical-treatment-bath-side discharge port. The
first liquid supply channel main body has two end portions on the
chemical treatment bath side. The first
chemical-treatment-bath-side discharge port is formed at one of the
end portions on the chemical treatment bath side of the first
liquid supply channel main body, and discharges the oxalate
treatment solution in the first liquid supply channel main body
into the first chemical treatment bath. The second
chemical-treatment-bath-side discharge port is formed at the other
of the end portions on the chemical treatment bath side of the
first liquid supply channel main body, and discharges the oxalate
treatment solution in the first liquid supply channel main body
into the second chemical treatment bath. Further, the second liquid
supply channel includes a second liquid supply channel main body, a
first chemical-treatment-bath-side inflow port and a second
chemical-treatment-bath-side inflow port. The second liquid supply
channel mail body has two end portions on the chemical treatment
bath side. The first chemical-treatment-bath-side inflow port is
formed at one of the end portions on the chemical treatment bath
side of the second liquid supply channel main body, and allows the
oxalate treatment solution in the first chemical treatment bath to
flow into the second liquid supply channel main body. The second
chemical-treatment-bath-side inflow port is formed at the other of
the end portions on the chemical treatment bath side of the second
liquid supply channel main body, and allows the oxalate treatment
solution in the second chemical treatment bath to flow into the
second liquid supply channel. In this case, the aforementioned flow
mechanism further includes a discharge port switching mechanism and
an inflow port switching mechanism. The discharge port switching
mechanism switches whether to cause the oxalate treatment solution
in the first liquid supply channel main body to be discharged from
the first chemical-treatment-bath-side discharge port or from the
second chemical-treatment-bath-side discharge port. The inflow port
switching mechanism switches whether to allow the oxalate treatment
solution to flow into the second liquid supply channel main body
from the first chemical-treatment-bath-side inflow port or from the
second chemical-treatment-bath-side inflow port.
[0093] The chemical treatment bath may include a first chemical
treatment bath and a second chemical treatment bath, and may use a
discharge port switching mechanism and an inflow port switching
mechanism to perform switching to cause either of the oxalate
treatment solution in the first chemical treatment bath and the
oxalate treatment solution in the second chemical treatment bath to
circulate. In this case, the oxalate treatment solution can be
caused to circulate in an alternate manner between the first
chemical treatment bath and the second chemical treatment bath.
[0094] Preferably, the flow mechanism includes an
under-regeneration-treatment-solution circulation channel that
causes the oxalate treatment solution in the treatment solution
regeneration bath to circulate. The
under-regeneration-treatment-solution circulation channel includes
an under-regeneration-treatment-solution circulation channel main
body, an under-regeneration-treatment-solution inflow port, an
under-regeneration-treatment-solution discharge port and an
under-regeneration-treatment-solution circulation driving source.
The under-regeneration-treatment-solution circulation channel main
body is capable of containing one part of the oxalate treatment
solution in the treatment solution regeneration bath, and has two
end portions. The under-regeneration-treatment-solution inflow port
is formed at one of the end portions of the
under-regeneration-treatment-solution circulation channel main
body, and allows the oxalate treatment solution in the treatment
solution regeneration bath to flow into the
under-regeneration-treatment-solution circulation channel main
body. The under-regeneration-treatment-solution discharge port is
formed at the other end portion of the
under-regeneration-treatment-solution circulation channel main
body, and discharges the oxalate treatment solution in the
under-regeneration-treatment-solution circulation channel main body
into the treatment solution regeneration bath. The
under-regeneration-treatment-solution circulation driving source
causes the oxalate treatment solution in the
under-regeneration-treatment-solution circulation channel main body
to move from the under-regeneration-treatment-solution inflow port
to the under-regeneration-treatment-solution discharge port. At
least one of the light source members is disposed between the
under-regeneration-treatment-solution inflow port and the
under-regeneration-treatment-solution discharge port.
[0095] By means of the under-regeneration-treatment-solution
circulation channel, the oxalate treatment solution in the
treatment solution regeneration bath repeatedly flows from the
under-regeneration-treatment-solution discharge port toward the
under-regeneration-treatment-solution inflow port. Because a light
source member is disposed between the
under-regeneration-treatment-solution discharge port and the
under-regeneration-treatment-solution inflow port, a larger amount
of the oxalate treatment solution is irradiated with light. As a
result, the oxalate treatment solution can be subjected to
regeneration treatment more efficiently.
[0096] Preferably, a bottom face of the treatment solution
regeneration bath is inclined.
[0097] As described above, when light is radiated to the chemical
treatment solution, insoluble iron (II) oxalate is generated. The
iron (II) oxalate forms precipitate and settles inside the
treatment solution regeneration bath. If the bottom face of the
treatment solution regeneration bath is inclined, the precipitate
accumulates at a lower location of the inclined bottom face. In
this case, it is easy to recover the precipitate.
[0098] The treatment solution regeneration bath may be partitioned
into a light irradiation chamber and a sedimentation chamber by a
partition member. The partition member has an opening portion that
connects the light irradiation chamber and the sedimentation
chamber. In this case, the one or more light source members are
disposed in the light irradiation chamber.
[0099] If the treatment solution regeneration bath is partitioned
into a light irradiation chamber and a sedimentation chamber, light
irradiation and removal of precipitate can be performed in separate
compartments. In this case, removal of the precipitate can be
performed more efficiently.
[0100] Preferably, the bottom face of the light irradiation chamber
becomes lower in the direction from the light irradiation chamber
toward the sedimentation chamber.
[0101] In a case where the bottom face of the light irradiation
chamber becomes lower in the direction from the light irradiation
chamber toward the sedimentation chamber, after precipitate that is
generated in the light irradiation chamber settles on the bottom
face of the light irradiation chamber, the precipitate moves under
its own weight to the sedimentation chamber. In this case, removal
of the precipitate can be performed more efficiently.
[0102] Preferably, the treatment solution regeneration bath further
includes a current direction changing member. The current direction
changing member is disposed so as to be immersible in the oxalate
treatment solution in the treatment solution regeneration bath, and
changes a direction of a flow of the oxalate treatment solution in
the treatment solution regeneration bath.
[0103] If the treatment solution regeneration bath includes a
current direction changing member, the directions of flows of the
oxalate treatment solution in the treatment solution regeneration
bath need not be uniformly aligned in a fixed direction, and a
turbulent flow can easily be generated. If a turbulent flow is
generated, the amount of oxalate treatment solution to be
irradiated with light increases. Therefore, the oxalate treatment
solution can be subjected to regeneration treatment more
efficiently.
[0104] Preferably, the light radiation apparatus is an ultraviolet
radiation apparatus.
[0105] By radiating light including a wavelength in the ultraviolet
range by means of an ultraviolet radiation apparatus, the oxalate
treatment solution can be regenerated more efficiently. The term
"wavelength in the ultraviolet range" refers to a wavelength in the
range of 10 to 400 nm.
[0106] The present embodiment will be described in detail below
with reference to the drawings. The same reference symbols will be
used throughout the drawings to refer to the same or like parts,
and description thereof will not be repeated.
FIRST EMBODIMENT
[Method for Producing Chemically Treated Alloy Material]
[0107] A method for producing a chemically treated alloy material
of the present embodiment includes a chemical treatment step and a
treatment solution regeneration step. In the chemical treatment
step, an alloy material is immersed in an oxalate treatment
solution containing oxalate ions and fluorine ions to perform a
chemical treatment. In the treatment solution regeneration step,
light is radiated to the oxalate treatment solution during the
chemical treatment and/or the oxalate treatment solution after the
chemical treatment. The method for producing a chemically treated
alloy material of the present embodiment uses, for example, the
following chemical treatment solution regeneration apparatus.
[Chemical Treatment Solution Regeneration Apparatus]
[0108] FIG. 3 is a schematic diagram of one example of a chemical
treatment solution regeneration apparatus 1 that is used in the
method for producing a chemically treated alloy material according
to the present embodiment. Referring to FIG. 3, the chemical
treatment solution regeneration apparatus 1 includes a treatment
solution regeneration bath 2 and a light radiation apparatus 3.
[Treatment Solution Regeneration Bath]
[0109] Referring to FIG. 3, the treatment solution regeneration
bath 2 is capable of containing an oxalate treatment solution 4
during chemical treatment of an alloy material 6 or after chemical
treatment of the alloy material 6. In FIG. 3, the treatment
solution regeneration bath 2 is a casing. The top face of the
treatment solution regeneration bath 2 may be open, or a top plate
may be provided at the top face. At least one part of a top plate
or a side face may be a member having translucency. The shape of
the treatment solution regeneration bath 2 is not particularly
limited as long as the treatment solution regeneration bath 2 is
capable of containing the oxalate treatment solution 4 during
chemical treatment or after chemical treatment of the alloy
material 6. The shape of the treatment solution regeneration bath 2
may be a rectangular parallelepiped shape, a cubic shape or a pipe
shape.
[0110] The oxalate treatment solution 4 which the treatment
solution regeneration bath 2 contains includes oxalate ions and
fluorine ions. As described later, the alloy material 6 may be
immersed in the treatment solution regeneration bath 2, and
regeneration of the oxalate treatment solution 4 in the treatment
solution regeneration bath 2 and chemical treatment of the alloy
material 6 may be performed at the same time. That is, the chemical
treatment solution regeneration apparatus 1 may function as a
chemical treatment apparatus for performing chemical treatment of
the alloy material 6. In this case, the treatment solution
regeneration bath 2 contains the oxalate treatment solution 4
during chemical treatment of the alloy material 6. In a case where
chemical treatment is not to be performed in the treatment solution
regeneration bath 2, the treatment solution regeneration bath 2
contains the oxalate treatment solution 4 after chemical treatment
of the alloy material 6. The oxalate treatment solution 4 which the
treatment solution regeneration bath 2 contains may be a mixture of
the oxalate treatment solution 4 during chemical treatment of the
alloy material 6 and the oxalate treatment solution 4 after
chemical treatment of the alloy material 6. Further, as described
later, in the case of performing a chemical treatment in the
treatment solution regeneration bath 2, in addition to the oxalate
treatment solution 4, the treatment solution regeneration bath 2 is
also capable of containing the alloy material 6 that is the object
of the chemical treatment.
[Light Radiation Apparatus]
[0111] The light radiation apparatus 3 includes a light source
member 31 and an unshown power supply apparatus. At least one part
of the light source member 31 is disposed inside the treatment
solution regeneration bath 2 or in the vicinity of the outside of
the treatment solution regeneration bath 2. The light source member
31 radiates light at the oxalate treatment solution 4. The light
radiation apparatus 3 radiates light at the oxalate treatment
solution 4 during chemical treatment or after chemical treatment to
thereby regenerate the oxalate treatment solution 4.
[0112] The light radiation apparatus 3 is disposed in a manner so
that the light radiation apparatus 3 is capable of radiating light
at the oxalate treatment solution 4 in the treatment solution
regeneration bath 2. The light source member 31 of the light
radiation apparatus 3 may be disposed inside the treatment solution
regeneration bath 2, as illustrated in FIG. 3, or may be disposed
on the outside of the treatment solution regeneration bath 2. In a
case where the light source member 31 is disposed inside the
treatment solution regeneration bath 2, although the light source
member 31 may be fixed without being immersed in the oxalate
treatment solution 4, it is preferable that the light source member
31 is disposed in a manner in which at least one part thereof is
immersible in the oxalate treatment solution 4 in the treatment
solution regeneration bath 2, and a configuration in which all of
the light source member 31 is immersed in the oxalate treatment
solution 4 is more preferable.
[0113] The light radiated from the light source member 31 is
attenuated when propagating through the atmosphere or through a
member having translucency. However, if at least one part of the
light source member 31 is immersed in the oxalate treatment
solution 4 in the treatment solution regeneration bath 2, the
distance between the light source and the oxalate treatment
solution 4 is shortened. Therefore, stronger light can be radiated
to the oxalate treatment solution 4. As a result, the oxalate
treatment solution 4 can be subjected to regeneration treatment
more efficiently.
[0114] A method for immersing the light source member 31 in the
oxalate treatment solution 4 is not particularly limited. For
example, the light source member 31 may be fixed, and a
predetermined amount of the oxalate treatment solution 4 may be
filled into the treatment solution regeneration bath 2 so as to
immerse at least one part of the light source member 31 in the
oxalate treatment solution 4. Further, for example, the light
radiation apparatus 3 may also include a driving source that moves
the light source member 31 in the vertical direction and/or
horizontal direction, and by moving the light source member 31 by
means of the driving source, the light source member 31 may be
immersed in the oxalate treatment solution 4 that was already
filled in the treatment solution regeneration bath 2.
[0115] In a case where the light source member 31 is fixed without
being immersed in the oxalate treatment solution 4, the light
source member 31 may be disposed, for example, at a position in the
treatment solution regeneration bath 2 that is a position above the
oxalate treatment solution 4. Specifically, in a case where a top
plate is attached to the treatment solution regeneration bath 2,
the light source member 31 may be attached to the surface on the
oxalate treatment solution 4 side of the top plate. In a case where
a top plate is not attached to the treatment solution regeneration
bath 2, the light source member 31 may be disposed at a position
above the oxalate treatment solution 4 that is a position on the
inner side of a side face of the treatment solution regeneration
bath 2.
[0116] The number, size and shape of the light source members 31
are not particularly limited. The number of the light source
members 31 may be one, as illustrated in FIG. 3, or may be more
than one.
[0117] A method for producing a chemically treated alloy material
according to the present embodiment using, for example, the
aforementioned chemical treatment solution regeneration apparatus 1
will now be described.
[Chemical Treatment Step]
[0118] In the chemical treatment step, the alloy material 6 is
immersed in the oxalate treatment solution 4 containing oxalate
ions and fluorine ions to perform a chemical treatment. First, the
oxalate treatment solution 4 is prepared and inserted into the
treatment solution regeneration bath 2.
[Oxalate Treatment Solution]
[0119] The oxalate treatment solution 4 contains oxalate ions and
fluorine ions. The oxalate treatment solution 4 is produced by
dissolving oxalic acid or a salt having an oxalate ion as an anion,
and a salt having a fluorine ion as an anion in a solvent. Examples
of a salt having an oxalate ion as an anion include one or two or
more types selected from the group consisting of sodium oxalate,
ammonium oxalate, potassium oxalate and iron (III) oxalate.
Examples of a salt having a fluorine ion as an anion include one or
two or more types selected from the group consisting of sodium
bifluoride, sodium fluoride, ammonium fluoride, potassium fluoride,
hydrogen fluoride, hydrofluoric acid and nitrogen fluoride. The
solvent may be, for example, water or a mixed solution of water and
an organic solvent. The organic solvent is, for example, an organic
solvent that is compatible with water.
[0120] The oxalate ion content of the oxalate treatment solution 4
is, for example, 1.0 to 50 g/L. A lower limit of the oxalate ion
content of the oxalate treatment solution 4 is preferably 5.0 g/L.
An upper limit of the oxalate ion content of the oxalate treatment
solution 4 is preferably 30 g/L. The fluorine ion content of the
oxalate treatment solution 4 is, for example, 0.1 to 10 g/L. A
lower limit of the fluorine ion content of the oxalate treatment
solution 4 is preferably 1.0 g/L. An upper limit of the fluorine
ion content of the oxalate treatment solution 4 is preferably 5.0
g/L. Next, the alloy material 6 is immersed in the oxalate
treatment solution 4.
[0121] As mentioned above, the oxalate treatment solution 4
contains oxalate ions, fluorine ions and a solvent. The oxalate
treatment solution 4 may also contain other components. Preferably,
the oxalate treatment solution 4 also contains an oxidizing agent.
The oxidizing agent is, for example, nitrate ions. An oxidation
reaction of hydrogen is promoted by nitrate ions. The oxidized
hydrogen disperses in the oxalate treatment solution 4 as water.
Nitrate ions can be contained in the oxalate treatment solution 4
by dissolving nitric acid or a salt having a nitrate ion as an
anion in the oxalate treatment solution 4. Examples of a salt
having a nitrate ion as an anion include one or two or more types
selected from the group consisting of ammonium nitrate, potassium
nitrate, calcium nitrate, iron nitrate, copper nitrate and sodium
nitrate. In addition, the oxidizing agent may contain one or two or
more types of substance selected from the group consisting of
permanganate and peroxide. The content of the oxidizing agent in
the oxalate treatment solution 4 is, for example, 0.1 to 20 g/L. An
upper limit of the content of the oxidizing agent in the oxalate
treatment solution 4 is preferably 10 g/L.
[0122] Preferably, the oxalate treatment solution 4 further
contains an accelerating agent. The accelerating agent is, for
example, thiosulfate ions. The thiosulfate ions react with
dissolved oxygen in the oxalate treatment solution 4 and decompose
into sulfuric acid. By this means, the amount of dissolved oxygen
in the oxalate treatment solution 4 is reduced and the chemical
treatment is accelerated. Thiosulfate ions can be contained in the
oxalate treatment solution 4 by dissolving a salt having a
thiosulfate ion as an anion in the oxalate treatment solution 4.
Examples of a salt having a thiosulfate ion as an anion include one
or two or more types selected from the group consisting of sodium
thiosulfate, ammonium thiosulfate, potassium thiosulfate and
calcium thiosulfate. The content of the accelerating agent in the
oxalate treatment solution 4 is, for example, 1.0 to 50 g/L. A
lower limit of the content of the accelerating agent in the oxalate
treatment solution 4 is preferably 10 g/L. An upper limit of the
content of the accelerating agent in the oxalate treatment solution
4 is preferably 40 g/L.
[0123] The chemical treatment is a well-known chemical treatment.
The temperature and time period of the chemical treatment can be
appropriately set. For example, the temperature of the chemical
treatment is within the range of 40 to 100.degree. C. A lower limit
of the temperature of the chemical treatment is preferably
80.degree. C. An upper limit of the temperature of the chemical
treatment is preferably 95.degree. C. For example, the time period
of the chemical treatment is within the range of 1 to 200 minutes.
A lower limit of the time period of the chemical treatment is
preferably five minutes. An upper limit of the time period of the
chemical treatment is preferably 20 minutes. The inside of the
treatment solution regeneration bath 2 may be stirred during the
chemical treatment or need not be stirred. The temperature of the
chemical treatment may be adjusted by heating the treatment
solution regeneration bath 2, or may be adjusted by immersing a
heat source inside the treatment solution regeneration bath 2. The
temperature of the chemical treatment may be adjusted by adding the
oxalate treatment solution 4 that was heated using an unshown
heating apparatus into the treatment solution regeneration bath
2.
[Treatment Solution Regeneration Step]
[0124] In the treatment solution regeneration step, the light
radiation apparatus 3 is used to radiate light at the oxalate
treatment solution 4 during chemical treatment and/or the oxalate
treatment solution 4 after chemical treatment. The oxalate
treatment solution 4 in the treatment solution regeneration bath 2
contains iron ions, oxalate ions and fluorine ions. When light is
radiated to the oxalate treatment solution 4, iron ions are reduced
and fluorine ions are released. By this means, the etching action
of fluorine ions is restored. In addition, when light is radiated
to the oxalate treatment solution 4, formation of iron (II) oxalate
is accelerated. The iron (II) oxalate formed as the result of light
irradiation precipitates. Thus, the iron ion content of the oxalate
treatment solution 4 decreases. When the iron ion content
decreases, it becomes difficult to form complexes between iron ions
and fluorine ions. Therefore, the action of the fluorine ions is
more actively maintained. As a result, a decrease in the chemical
treatability can be suppressed even in a case where chemical
treatment is repeatedly performed.
[0125] In the case of the production method including the above
steps, a decrease in chemical treatability can be suppressed even
in a case where chemical treatment is repeatedly performed.
[Oxalate Ion Addition Step]
[0126] The production method described above may also include an
oxalate ion addition step. In the treatment solution regeneration
step, oxalate ions are consumed as the iron ion content of the
oxalate treatment solution 4 decreases. If the production method
includes a step of adding oxalate ions, consumed oxalate ions are
replenished. Addition of oxalate ions is performed by dissolving
oxalic acid or a salt having an oxalate ion as an anion in the
oxalate treatment solution 4. Alternatively, the addition of
oxalate ions is performed by adding a solution in which oxalate
ions were dissolved to the oxalate treatment solution 4. Examples
of salts having an oxalate ion as an anion include one or two or
more types of salt selected from the group consisting of sodium
oxalate, ammonium oxalate, potassium oxalate and iron (III)
oxalate. By this means, the oxalate ion content of the oxalate
treatment solution 4 increases. As a result, it becomes easy for
oxalate ions to react with iron (divalent iron ions) that dissolved
on the surface of the alloy material 6, and the chemical treatment
is accelerated. The concentration of the added oxalate ions can be
appropriately set.
[0127] The time point at which to perform the oxalate ion addition
step is not particularly limited. The oxalate ion addition step may
be performed before the chemical treatment step, may be performed
during the chemical treatment step, or may be performed after the
chemical treatment. The oxalate ion addition step may be performed
at a time point that is after the chemical treatment and before the
treatment solution regeneration step, or may be performed during
the treatment solution regeneration step, or may be performed after
the treatment solution regeneration step.
[Other Steps]
[0128] The production method described above may also include a
preparation step of preparing the alloy material 6 before the
chemical treatment step. The term "preparation" refers to, for
example, shotblasting, pickling or degreasing. A lubrication
coating may be formed on the surface of the chemically treated
alloy material produced by the above described production method.
The lubrication coating is, for example, metallic soap.
[Wavelengths of Light]
[0129] In a case where wavelengths of the light in the treatment
solution regeneration step are short wavelengths of high intensity,
the decomposition reaction of iron (III) oxalate to iron (II)
oxalate is further accelerated. Therefore, preferably the
wavelengths of the light include a wavelength in the ultraviolet
range. If the wavelengths of the light include a wavelength in the
ultraviolet range, an etching action of fluorine ions can be
restored more efficiently, and the iron ion content of the oxalate
treatment solution 4 can be reduced more efficiently. Here, the
term "wavelength in the ultraviolet range" refers to a wavelength
in the range of 10 to 400 nm.
[Alloy Material]
[0130] The shape of the alloy material 6 is not particularly
limited as long as the shape is such that an oxalate coating can be
formed. The shape of the alloy material 6 is, for example, the
shape of a plate, a pipe, a bar, a wire rod, a sphere, die steel,
another alloy material for construction or a machine construction
component, a gear, a connecting rod, a crankshaft, a piston or
another automobile component. The method for producing a chemically
treated alloy material of the present embodiment can be favorably
applied to a case where the shape of the alloy material 6 is a pipe
shape.
[0131] The chemical composition of the alloy material 6 contains
Fe. It suffices that the chemical composition of the alloy material
6 contains Fe. That is, the alloy material 6 may be a steel
material that contains 50% or more of Fe. In this case, the alloy
material 6 may contain 10.5% or more of Cr. An oxide film that has
high corrosion resistance is formed on the surface of the alloy
material 6 that contains 10.5% or more of Cr. According to the
method for producing a chemically treated alloy material of the
present embodiment, the action of fluorine ions is actively
maintained. Therefore, a chemically treated alloy material can be
produced even when using the alloy material 6 having an oxide film
formed on the surface. The method for producing a chemically
treated alloy material of the present embodiment can be favorably
used for the alloy material 6 that contains 10.5% or more of Cr. In
addition, the alloy material 6 may be, for example, an Ni-based
alloy or an Ni--Cr--Fe alloy. The method for producing a chemically
treated alloy material of the present embodiment can also be
favorably used for the alloy material 6 in which the total content
of Cr and/or Ni is more than 50% (that is, the alloy material 6 in
which the Fe content is less than 50%).
SECOND EMBODIMENT
[Method for Producing Chemically Treated Alloy Material]
[0132] Preferably, in the aforementioned treatment solution
regeneration step, light is radiated to the oxalate treatment
solution 4 while causing the oxalate treatment solution 4 in the
treatment solution regeneration bath 2 to flow. By causing the
oxalate treatment solution 4 in the treatment solution regeneration
bath 2 to flow, the amount of the oxalate treatment solution 4 to
be irradiated with light increases. As a result, the oxalate
treatment solution 4 can be subjected to regeneration treatment
more efficiently, and hence a decrease in chemical treatability can
be suppressed more efficiently. For example, if the chemical
treatment solution regeneration apparatus 1 that is described
hereunder is used, the treatment solution regeneration step can be
executed while causing the oxalate treatment solution 4 to
flow.
[Chemical Treatment Solution Regeneration Apparatus]
[0133] Preferably, the chemical treatment solution regeneration
apparatus 1 further includes a flow mechanism that causes the
oxalate treatment solution 4 in the treatment solution regeneration
bath 2 to flow.
[Flow Mechanism]
[0134] The flow mechanism is not particularly limited as long as
the flow mechanism is a mechanism capable of causing the oxalate
treatment solution 4 in the treatment solution regeneration bath 2
to flow. FIG. 4 is a schematic diagram of a chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different from FIG. 3. Referring to FIG. 4, in addition to
the treatment solution regeneration bath 2 and the light radiation
apparatus 3, the chemical treatment solution regeneration apparatus
1 includes a flow mechanism 7. For example, as illustrated in FIG.
4, the flow mechanism 7 is an apparatus that is attached to a
rotary shaft, and generates a flow in the rotary shaft direction by
rotation of a blade having a helicoidal surface around the rotary
shaft. The flow mechanism 7 is, for example, a screw or a
propeller.
[0135] However, the flow mechanism 7 may be another kind of
mechanism. The flow mechanism 7, for example, may be a mechanism
that causes the oxalate treatment solution 4 to circulate. The flow
mechanism 7 for example, may be a mechanism that utilizes a pump to
pump up some of the oxalate treatment solution 4 in the treatment
solution regeneration bath 2, and returns the pumped-up oxalate
treatment solution 4 into the treatment solution regeneration bath
2 utilizing a height difference. The flow mechanism 7, for example,
may be a mechanism that includes a heating apparatus inside the
treatment solution regeneration bath 2, and causes the oxalate
treatment solution 4 which was heated by the heating apparatus to
flow by convection.
[0136] The number and arrangement of flow mechanisms 7 is not
particularly limited. The number of flow mechanisms 7 may be one or
may be more than one. A direction in which the oxalate treatment
solution 4 is caused to flow by the flow mechanism 7 may be the
horizontal direction, may be a perpendicular direction from above
to below, may be a perpendicular direction from below to above, or
may be a direction that is inclined with respect to the horizontal
direction. The oxalate treatment solution 4 may be caused to flow
in one direction by the flow mechanism 7, or flows of the oxalate
treatment solution 4 in different directions may be generated by
flow mechanisms 7 that are oriented in different directions. In
short, it suffices that the amount of the oxalate treatment
solution 4 to be irradiated with light from the light source member
31 can be increased. Accordingly, directions in which the oxalate
treatment solution 4 is caused to flow by the flow mechanism 7
include at least a direction toward the light source member 31.
[0137] A method for producing a chemically treated alloy material
that uses, for example, the chemical treatment solution
regeneration apparatus 1 described above will now be described.
[Chemical Treatment Step]
[0138] The chemical treatment step is the same as in the first
embodiment.
[Treatment Solution Regeneration Step]
[0139] In a case where the chemical treatment solution regeneration
apparatus 1 includes the flow mechanism 7, during the treatment
solution regeneration step, the oxalate treatment solution 4 in the
treatment solution regeneration bath 2 is caused to flow by the
flow mechanism 7. The greater that the amount of the oxalate
treatment solution 4 that is caused to flow is, the more that the
amount of the oxalate treatment solution 4 to be irradiated with
light can be increased. Therefore, the oxalate treatment solution 4
can be subjected to regeneration treatment more efficiently. For
example, by increasing the speed at which the oxalate treatment
solution 4 is caused to flow by the flow mechanism 7, a greater
amount of the oxalate treatment solution 4 can be irradiated with
light. In addition, by increasing the amount of the oxalate
treatment solution 4 that flows at one time by providing a
plurality of the flow mechanisms 7 and causing the plurality of the
flow mechanisms 7 to operate simultaneously, a greater amount of
the oxalate treatment solution 4 can be irradiated with light.
[0140] By means of the method described above, in the treatment
solution regeneration step, light can be radiated to the oxalate
treatment solution 4 while causing the oxalate treatment solution 4
in the treatment solution regeneration bath 2 to flow.
[0141] The method for producing a chemically treated alloy material
of the present disclosure can also be implemented by an apparatus
other than the apparatuses illustrated in FIG. 3 and FIG. 4.
Hereunder, examples of the chemical treatment solution regeneration
apparatus 1 that are capable of implementing the method for
producing a chemically treated alloy material of the present
disclosure are described.
THIRD EMBODIMENT
[0142] The chemical treatment solution regeneration apparatus 1 may
have a chemical treatment bath 5 in addition to the treatment
solution regeneration bath 2. In such case, chemical treatment of
the alloy material 6 and regeneration treatment of the oxalate
treatment solution 4 are performed in separate baths. In a case
where the chemical treatment solution regeneration apparatus 1
includes the chemical treatment bath 5 that is separate from the
treatment solution regeneration bath 2, the flow mechanism 7 may
have a first liquid supply channel and a second liquid supply
channel. FIG. 5 is a schematic diagram of the chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different to the embodiments illustrated in FIG. 3 and FIG.
4. The arrows in FIG. 5 indicate the direction in which the oxalate
treatment solution 4 circulates. Referring to FIG. 5, the chemical
treatment solution regeneration apparatus 1 includes the treatment
solution regeneration bath 2, the light radiation apparatus 3, the
chemical treatment bath 5 and the flow mechanism 7. The flow
mechanism 7 includes a first liquid supply channel 71 that conveys
the oxalate treatment solution 4 in the treatment solution
regeneration bath 2 to the chemical treatment bath 5, and a second
liquid supply channel 72 that conveys the oxalate treatment
solution 4 in the chemical treatment bath 5 to the treatment
solution regeneration bath 2. The chemical treatment solution
regeneration apparatus 1 circulates the oxalate treatment solution
4 between the chemical treatment bath 5 and the treatment solution
regeneration bath 2 by means of the first liquid supply channel 71
and the second liquid supply channel 72. By this means, even in the
case of performing chemical treatments in succession, a decrease in
chemical treatability can be suppressed.
[Chemical Treatment Bath]
[0143] The chemical treatment bath 5 is capable of containing the
oxalate treatment solution 4 after being irradiated with light by
the light radiation apparatus 3 in the treatment solution
regeneration bath 2. In the chemical treatment bath 5, a chemical
treatment in which the alloy material 6 is immersed in the oxalate
treatment solution 4 contained therein can be performed. In FIG. 5,
the chemical treatment bath 5 has a rectangular
parallelepiped-shaped casing. The top face of the chemical
treatment bath 5 may be open, or a top plate may be provided at the
top face. The shape of the chemical treatment bath 5 may be a
rectangular parallelepiped shape, a cubic shape, or the shape of a
casing that has a circular bottom face like a bucket. Further, the
number of chemical treatment baths 5 is not particularly
limited.
[First Liquid Supply Channel]
[0144] The first liquid supply channel 71 connects the treatment
solution regeneration bath 2 and the chemical treatment bath 5, and
conveys the oxalate treatment solution 4 from the treatment
solution regeneration bath 2 to the chemical treatment bath 5. The
first liquid supply channel 71 includes a first liquid supply
channel main body 710, a treatment-solution-regeneration-bath-side
inflow port 711 that is formed at one of the end portions of the
first liquid supply channel main body 710, and a
chemical-treatment-bath-side discharge port 712 that is formed at
the other end portion of the first liquid supply channel main body
710. The first liquid supply channel 71 may further include a first
liquid supply channel driving source 713.
[First Liquid Supply Channel Main Body]
[0145] The shape of the first liquid supply channel main body 710
is, for example, tubular. A filter for collecting precipitate, or a
valve that inhibits a back flow of the oxalate treatment solution 4
may be provided inside the first liquid supply channel main body
710.
[Treatment-Solution-Regeneration-Bath-Side Inflow Port]
[0146] The treatment-solution-regeneration-bath-side inflow port
711 is formed at an end portion on the treatment solution
regeneration bath 2 side of the first liquid supply channel main
body 710. The treatment-solution-regeneration-bath-side inflow port
711 allows the oxalate treatment solution 4 in the treatment
solution regeneration bath 2 to flow into the first liquid supply
channel main body 710. Preferably, the
treatment-solution-regeneration-bath-side inflow port 711 is
disposed further downstream than the center position of the
treatment solution regeneration bath 2. A filter for inhibiting the
flow of precipitate or other foreign substances into the first
liquid supply channel main body 710 may be provided in the
treatment-solution-regeneration-bath-side inflow port 711.
[Chemical-Treatment-Bath-Side Discharge Port]
[0147] The chemical-treatment-bath-side discharge port 712 is
formed at an end portion on the chemical treatment bath 5 side of
the first liquid supply channel main body 710. The
chemical-treatment-bath-side discharge port 712 discharges the
oxalate treatment solution 4 in the first liquid supply channel
main body 710 into the chemical treatment bath 5. Preferably, the
chemical-treatment-bath-side discharge port 712 is disposed further
upstream than the center position of the chemical treatment bath 5.
In this case, the oxalate treatment solution 4 in the chemical
treatment bath 5 can be caused to circulate more efficiently.
[First Liquid Supply Channel Driving Source]
[0148] The first liquid supply channel driving source 713 causes
the oxalate treatment solution 4 in the first liquid supply channel
main body 710 to move from the
treatment-solution-regeneration-bath-side inflow port 711 to the
chemical-treatment-bath-side discharge port 712. The first liquid
supply channel driving source 713 is not particularly limited as
long as the first liquid supply channel driving source 713 is
capable of moving the oxalate treatment solution 4. The first
liquid supply channel driving source 713 is, for example, a
pump.
[Second Liquid Supply Channel]
[0149] The second liquid supply channel 72 connects the chemical
treatment bath 5 and the treatment solution regeneration bath 2,
and conveys the oxalate treatment solution 4 from the chemical
treatment bath 5 to the treatment solution regeneration bath 2. The
second liquid supply channel 72 includes a second liquid supply
channel main body 720, a chemical-treatment-bath-side inflow port
721 that is formed at one of the end portions of the second liquid
supply channel main body 720, and a
treatment-solution-regeneration-bath-side discharge port 722 that
is formed at the other end portion of the second liquid supply
channel main body 720. The second liquid supply channel 72 may
further include a second liquid supply channel driving source
723.
[Second Liquid Supply Channel Main Body]
[0150] The shape of the second liquid supply channel main body 720
is, for example, tubular. A filter for collecting precipitate or
other foreign substances, or a valve that inhibits a back flow of
the oxalate treatment solution 4 may be provided inside the second
liquid supply channel main body 720.
[Chemical-Treatment-Bath-Side Inflow Port]
[0151] The chemical-treatment-bath-side inflow port 721 is formed
at an end portion on the chemical treatment bath 5 side of the
second liquid supply channel main body 720. The
chemical-treatment-bath-side inflow port 721 allows the oxalate
treatment solution 4 in the chemical treatment bath 5 to flow into
the second liquid supply channel main body 720. Preferably, the
chemical-treatment-bath-side inflow port 721 is disposed further
downstream than the center position of the chemical treatment bath
5. In this case, the oxalate treatment solution 4 in the chemical
treatment bath 5 can be caused to circulate more efficiently.
[Treatment-Solution-Regeneration-Bath-Side Discharge Port]
[0152] The treatment-solution-regeneration-bath-side discharge port
722 is formed at an end portion on the treatment solution
regeneration bath 2 side of the second liquid supply channel main
body 720. The treatment-solution-regeneration-bath-side discharge
port 722 discharges the oxalate treatment solution 4 in the second
liquid supply channel main body 720 into the treatment solution
regeneration bath 2. Preferably, the
treatment-solution-regeneration-bath-side discharge port 722 is
disposed further upstream than the center position of the treatment
solution regeneration bath 2.
[Second Liquid Supply Channel Driving Source]
[0153] The second liquid supply channel driving source 723 causes
the oxalate treatment solution 4 in the second liquid supply
channel main body 720 to move from the chemical-treatment-bath-side
inflow port 721 to the treatment-solution-regeneration-bath-side
discharge port 722. The second liquid supply channel driving source
723 is not particularly limited as long as the second liquid supply
channel driving source 723 is capable of moving the oxalate
treatment solution 4. The second liquid supply channel driving
source 723 is, for example, a pump.
[0154] In a case where the chemical treatment solution regeneration
apparatus 1 includes a plurality of the chemical treatment baths 5,
the first liquid supply channel 71 may be connected to each of the
plurality of chemical treatment baths 5, and may convey the oxalate
treatment solution 4 in the treatment solution regeneration bath 2
to each of the chemical treatment baths 5. Further, as described
later, a single first liquid supply channel 71 that is connected to
the treatment solution regeneration bath 2 may branch at a position
along the single first liquid supply channel 71 and convey the
oxalate treatment solution 4 to each of the chemical treatment
baths 5. The same applies with respect to the second liquid supply
channel 72. The second liquid supply channel 72 may be connected to
each of the chemical treatment baths 5, and the oxalate treatment
solution 4 from the respective chemical treatment baths 5 may be
conveyed to the same treatment solution regeneration bath 2. A
configuration may also be adopted in which second liquid supply
channels 72 that are connected to the respective chemical treatment
baths 5 merge at a partway position.
[0155] In FIG. 5, the first liquid supply channel driving source
713 is disposed on the first liquid supply channel 71, and the
second liquid supply channel driving source 723 is disposed on the
second liquid supply channel 72. However, the number and
arrangement of the first liquid supply channel driving source 713
and the second liquid supply channel driving source 723 are not
limited to the example illustrated in FIG. 5. For example, either
one of the first liquid supply channel driving source 713 and the
second liquid supply channel driving source 723 need not be
provided. For example, in a case where a height difference is
provided between the installation location of the chemical
treatment bath 5 and the installation location of the treatment
solution regeneration bath 2, and the oxalate treatment solution 4
is caused to flow by utilizing the height difference, the first
liquid supply channel driving source 713 or the second liquid
supply channel driving source 723 may be disposed only on the
liquid supply channel which has the lowest place among the entire
first liquid supply channel 71 or the entire second liquid supply
channel 72.
[0156] The oxalate treatment solution 4 that was irradiated with
light within the treatment solution regeneration bath 2 is conveyed
by the first liquid supply channel 71 to the chemical treatment
bath 5. Thus, in the chemical treatment bath 5, chemical treatment
can be carried out utilizing the oxalate treatment solution 4 that
underwent regeneration treatment. The oxalate treatment solution 4
which deteriorated inside the chemical treatment bath 5 is conveyed
by the second liquid supply channel 72 to the treatment solution
regeneration bath 2. Inside the treatment solution regeneration
bath 2, the oxalate treatment solution 4 is regenerated by light
irradiation. The oxalate treatment solution 4 that underwent the
regeneration treatment is conveyed once more by the first liquid
supply channel 71 to the chemical treatment bath 5. By causing the
oxalate treatment solution 4 to circulate between the treatment
solution regeneration bath 2 and the chemical treatment bath 5 in
this manner, a decrease in chemical treatability can be suppressed
even in the case of performing chemical treatments in
succession.
[0157] The arrangement of the treatment solution regeneration bath
2, the light radiation apparatus 3, the chemical treatment bath 5,
the first liquid supply channel 71 and the second liquid supply
channel 72 is not limited to the example illustrated in FIG. 5 as
long as the arrangement of these components satisfies the
aforementioned conditions. FIG. 6 is a schematic diagram of the
chemical treatment solution regeneration apparatus 1 according to
another embodiment that is different from FIG. 3 to FIG. 5.
Although in FIG. 5 the light source member 31 of the light
radiation apparatus 3 is disposed at a position such that one part
thereof is immersed in the oxalate treatment solution 4 in the
treatment solution regeneration bath 2, in FIG. 6 the light source
member 31 is disposed in the vicinity of the outside of the
treatment solution regeneration bath 2.
[0158] As described above, the method for producing a chemically
treated alloy material of the present disclosure can also be
carried out using the chemical treatment solution regeneration
apparatus 1 that includes the chemical treatment bath 5, the first
liquid supply channel 71 and the second liquid supply channel 72.
In this case, in the treatment solution regeneration step, the
oxalate treatment solution 4 is caused to circulate between the
treatment solution regeneration bath 2 and the chemical treatment
bath 5 using the first liquid supply channel 71 and the second
liquid supply channel 72.
FOURTH EMBODIMENT
[0159] As described above, a plurality of the chemical treatment
baths 5 may be provided. For example, the chemical treatment baths
5 may include a first chemical treatment bath 51 and a second
chemical treatment bath 52. In addition, a discharge port switching
mechanism and an inflow port switching mechanism may be used to
switch between the oxalate treatment solutions 4 in the chemical
treatment baths to be circulated. In this case, the oxalate
treatment solutions 4 in the first chemical treatment bath 51 and
the second chemical treatment bath 52 can be caused to circulate in
an alternating manner.
[0160] FIG. 7 is a schematic diagram of the chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different from FIG. 3 to FIG. 6. In a case where the
chemical treatment baths 5 include the first chemical treatment
bath 51 and the second chemical treatment bath 52, the first liquid
supply channel main body 710 may include two end portions on the
chemical treatment bath 5 side. A discharge port is formed at the
two end portions on the chemical treatment bath 5 side of the first
liquid supply channel main body 710. Specifically, the first liquid
supply channel 71 includes the first liquid supply channel main
body 710, a first chemical-treatment-bath-side discharge port 714
and a second chemical-treatment-bath-side discharge port 715. The
first chemical-treatment-bath-side discharge port 714 is formed at
one of the end portions on the chemical treatment bath 5 side of
the first liquid supply channel main body 710, and discharges the
oxalate treatment solution 4 in the first liquid supply channel
main body 710 into the first chemical treatment bath 51. The second
chemical-treatment-bath-side discharge port 715 is formed at the
other end portion on the chemical treatment bath 5 side of the
first liquid supply channel main body 710, and discharges the
oxalate treatment solution 4 in the first liquid supply channel
main body 710 into the second chemical treatment bath 52. The two
end portions on the chemical treatment bath 5 side of the first
liquid supply channel 71 may be formed in a manner in which the
first liquid supply channel main body 710 branches at a partway
position as illustrated in FIG. 7, or a configuration may be
adopted in which two of the first liquid supply channels 71 are
provided, and the two end portions are the end portions of the two
first liquid supply channels 71, respectively.
[0161] In a case where the chemical treatment baths 5 include the
first chemical treatment bath 51 and the second chemical treatment
bath 52, the second liquid supply channel main body 720 may include
two end portions on the chemical treatment bath 5 side. An inflow
port is formed at each of the two end portions on the chemical
treatment bath 5 side of the second liquid supply channel main body
720. Specifically, the second liquid supply channel 72 includes the
second liquid supply channel main body 720, a first
chemical-treatment-bath-side inflow port 724 and a second
chemical-treatment-bath-side inflow port 725. The first
chemical-treatment-bath-side inflow port 724 is formed at one of
the end portions on the chemical treatment bath 5 side of the
second liquid supply channel main body 720, and allows the oxalate
treatment solution 4 in the first chemical treatment bath 51 to
flow into the second liquid supply channel main body 720. The
second chemical-treatment-bath-side inflow port 725 is formed at
the other of the end portions on the chemical treatment bath 5 side
of the second liquid supply channel main body 720, and allows the
oxalate treatment solution 4 in the second chemical treatment bath
52 to flow into the second liquid supply channel main body 720. The
two end portions of the second liquid supply channel 72 may be
formed in a manner in which the second liquid supply channel main
body 720 branches at a partway position as illustrated in FIG. 7,
or a configuration may be adopted in which two of the second liquid
supply channels 72 are provided, and the two end portions are the
end portions of the two second liquid supply channels 72,
respectively.
[0162] Referring to FIG. 7, preferably the flow mechanism 7 also
includes a discharge port switching mechanism 716 and an inflow
port switching mechanism 726. The discharge port switching
mechanism 716 switches whether to cause the oxalate treatment
solution 4 in the first liquid supply channel main body 710 to be
discharged from the first chemical-treatment-bath-side discharge
port 714 or from the second chemical-treatment-bath-side discharge
port 715. The inflow port switching mechanism 726 switches whether
to cause the oxalate treatment solution 4 to flow into the second
liquid supply channel main body 720 from the first
chemical-treatment-bath-side inflow port 724 or from the second
chemical-treatment-bath-side inflow port 725.
[0163] The discharge port switching mechanism 716 and the inflow
port switching mechanism 726 are not particularly limited as long
as a flow of the oxalate treatment solution 4 can be switched. The
discharge port switching mechanism 716 is, for example, a valve.
Referring to FIG. 7, two valves are provided that are disposed on
the first chemical treatment bath 51 side and on the second
chemical treatment bath 52 side on the branched first liquid supply
channel main body 710, respectively. The discharge port switching
mechanism 716 may also be a pump. In this case, the first liquid
supply channel driving source 713 (pump) is not required.
[0164] The inflow port switching mechanism 726 is, for example, a
valve. Referring to FIG. 7, two valves are provided that are
disposed on the first chemical treatment bath 51 side and on the
second chemical treatment bath 52 side on the branched second
liquid supply channel main body 720, respectively. The inflow port
switching mechanism 726 may also be a pump. In this case, the
second liquid supply channel driving source 723 (pump) is not
required.
FIFTH EMBODIMENT
[0165] In the third and fourth embodiments, the chemical treatment
solution regeneration apparatus 1 includes the chemical treatment
bath 5, and the flow mechanism 7 causes the oxalate treatment
solution 4 as a whole to circulate between the chemical treatment
bath 5 and the treatment solution regeneration bath 2. On the other
hand, the flow mechanism 7 causes the oxalate treatment solution 4
in the treatment solution regeneration bath 2 to circulate.
[0166] FIG. 8 is a schematic diagram of the chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different from FIG. 3 to FIG. 7. Referring to FIG. 8, the
chemical treatment solution regeneration apparatus 1 includes the
treatment solution regeneration bath 2, the light radiation
apparatus 3 and the flow mechanism 7. The flow mechanism 7 includes
an under-regeneration-treatment-solution circulation channel 73
that causes the oxalate treatment solution 4 within the treatment
solution regeneration bath 2 to circulate.
[Under-Regeneration-Treatment-Solution Circulation Channel]
[0167] The under-regeneration-treatment-solution circulation
channel 73 includes an under-regeneration-treatment-solution
circulation channel main body 730, an
under-regeneration-treatment-solution inflow port 731 and an
under-regeneration-treatment-solution discharge port 732. At least
one light source member 31 is disposed between the
under-regeneration-treatment-solution inflow port 731 and the
under-regeneration-treatment-solution discharge port 732. The
under-regeneration-treatment-solution circulation channel 73 also
includes an under-regeneration-treatment-solution circulation
driving source 733.
[0168] By means of the under-regeneration-treatment-solution
circulation channel 73, the oxalate treatment solution 4 in the
treatment solution regeneration bath 2 is caused to repeatedly flow
from the under-regeneration-treatment-solution discharge port 732
toward the under-regeneration-treatment-solution inflow port 731.
Therefore, the occasions at which the oxalate treatment solution 4
is irradiated with light from the light source member 31 that is
disposed between the under-regeneration-treatment-solution
discharge port 732 and the under-regeneration-treatment-solution
inflow port 731 increase. As a result, the oxalate treatment
solution 4 can be subjected to regeneration treatment more
efficiently.
[Under-Regeneration-Treatment-Solution Circulation Channel Main
Body]
[0169] The shape of the under-regeneration-treatment-solution
circulation channel main body 730 is not particularly limited. The
shape of the under-regeneration-treatment-solution circulation
channel main body 730 is, for example, tubular. A filter for
collecting precipitate or other foreign substances, or a valve that
inhibits a back flow of the oxalate treatment solution 4 may be
provided in the under-regeneration-treatment-solution circulation
channel main body 730.
[Under-Regeneration-Treatment-Solution Inflow Port]
[0170] The under-regeneration-treatment-solution inflow port 731 is
formed at one of the end portions of the
under-regeneration-treatment-solution circulation channel main body
730, and allows the oxalate treatment solution 4 in the treatment
solution regeneration bath 2 to flow into the
under-regeneration-treatment-solution circulation channel main body
730. A filter for inhibiting precipitate from flowing into the
under-regeneration-treatment-solution circulation channel main body
730, or a valve that inhibits a back flow of the oxalate treatment
solution 4 may be provided in the
under-regeneration-treatment-solution inflow port 731.
[Under-Regeneration-Treatment-Solution Discharge Port]
[0171] The under-regeneration-treatment-solution discharge port 732
is formed at the other end portion of the
under-regeneration-treatment-solution circulation channel main body
730, and discharges the oxalate treatment solution 4 that is in the
under-regeneration-treatment-solution circulation channel main body
730. The under-regeneration-treatment-solution discharge port 732
may be disposed so as to be immersible in the oxalate treatment
solution 4 in the treatment solution regeneration bath 2 as
illustrated in FIG. 8, or a hole that penetrates a side face of the
treatment solution regeneration bath 2 may be provided and the
under-regeneration-treatment-solution discharge port 732 may be
disposed in a manner in which the
under-regeneration-treatment-solution discharge port 732 is
connected to the hole, or the under-regeneration-treatment-solution
discharge port 732 may be disposed above the treatment solution
regeneration bath 2. As illustrated in FIG. 8, an ejection nozzle
for increasing the discharge speed of the oxalate treatment
solution 4 may be provided in the
under-regeneration-treatment-solution discharge port 732.
[Under-Regeneration-Treatment-Solution Circulation Driving
Source]
[0172] The under-regeneration-treatment-solution circulation
driving source 733 causes the oxalate treatment solution 4 in the
under-regeneration-treatment-solution circulation channel main body
730 to move from the under-regeneration-treatment-solution inflow
port 731 to the under-regeneration-treatment-solution discharge
port 732. The under-regeneration-treatment-solution circulation
driving source 733 is, for example, a pump.
[0173] At least one light source member 31 is disposed between the
under-regeneration-treatment-solution discharge port 732 and the
under-regeneration-treatment-solution inflow port 731. In a case
where a plurality of the light source members 31 are disposed,
preferably all of the light source members 31 are disposed between
the under-regeneration-treatment-solution discharge port 732 and
the under-regeneration-treatment-solution inflow port 731. In this
case, the amount of the oxalate treatment solution 4 to be
irradiated with light while the oxalate treatment solution 4 flows
from the under-regeneration-treatment-solution discharge port 732
to the under-regeneration-treatment-solution inflow port 731
increases.
[0174] The number of under-regeneration-treatment-solution
circulation channels 73 is not particularly limited. One
under-regeneration-treatment-solution circulation channel 73 may be
provided as illustrated in FIG. 8, or a plurality of the
under-regeneration-treatment-solution circulation channels 73 may
be provided. In a case where a plurality of the
under-regeneration-treatment-solution circulation channels 73 are
provided, the direction in which the oxalate treatment solution 4
is circulated may be the same or different for each of the
under-regeneration-treatment-solution circulation channels 73. In a
case where a plurality of the under-regeneration-treatment-solution
circulation channels 73 are provided, the respective
under-regeneration-treatment-solution circulation channels 73 may
operate simultaneously or may operate at different times from each
other.
SIXTH EMBODIMENT
[0175] In a case where the flow mechanism 7 includes the
under-regeneration-treatment-solution circulation channel 73 also,
the chemical treatment solution regeneration apparatus 1 may have a
configuration in which the chemical treatment bath 5 is provided in
addition to the treatment solution regeneration bath 2, and
chemical treatment of the alloy material 6 and regeneration
treatment of the oxalate treatment solution 4 can be performed
separately to each other. In this case, preferably the chemical
treatment solution regeneration apparatus 1 includes the
under-regeneration-treatment-solution circulation channel 73 which
causes the oxalate treatment solution 4 in the treatment solution
regeneration bath 2 to circulate, and the first liquid supply
channel 71 and the second liquid supply channel 72 which cause the
entire oxalate treatment solution 4 to circulate, including the
oxalate treatment solution 4 in the chemical treatment bath 5.
[0176] FIG. 9 is a schematic diagram of the chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different from FIG. 3 to FIG. 8. Referring to FIG. 9, the
chemical treatment solution regeneration apparatus 1 includes the
treatment solution regeneration bath 2, the light radiation
apparatus 3, the chemical treatment bath 5 and the flow mechanism
7. The flow mechanism 7 includes the first liquid supply channel
71, the second liquid supply channel 72 and the
under-regeneration-treatment-solution circulation channel 73.
[0177] In a case where the chemical treatment solution regeneration
apparatus 1 includes the chemical treatment bath 5, and the flow
mechanism 7 includes the under-regeneration-treatment-solution
circulation channel 73 in addition to the first liquid supply
channel 71 and the second liquid supply channel 72, the oxalate
treatment solution 4 that is repeatedly irradiated with light
inside the treatment solution regeneration bath 2 can be circulated
to the chemical treatment bath 5. In this case, because the
occasions at which the oxalate treatment solution 4 is irradiated
with light from the light source member 31 increase, and the amount
of the oxalate treatment solution 4 to be irradiated with light
increase, a decrease in the chemical treatability can be further
suppressed.
[0178] The flow rate in the first liquid supply channel 71 and in
the second liquid supply channel 72 may be the same as or different
from the flow rate in the under-regeneration-treatment-solution
circulation channel 73. By having the
under-regeneration-treatment-solution circulation channel 73, light
is repeatedly radiated to the oxalate treatment solution 4 in the
treatment solution regeneration bath 2. Therefore, even if the flow
rate in the first liquid supply channel 71 and the second liquid
supply channel 72 is slow, the oxalate treatment solution 4 can be
efficiently subjected to regeneration treatment. Further, by
speeding up the flow rate in the first liquid supply channel 71 and
the second liquid supply channel 72, and/or the
under-regeneration-treatment-solution circulation channel 73, the
amount of the oxalate treatment solution 4 to be irradiated with
light is increased, and the oxalate treatment solution 4 can be
more efficiently subjected to regeneration treatment. For example,
in a case where the flow rate in the
under-regeneration-treatment-solution circulation channel 73 is
made a fast flow rate, the oxalate treatment solution 4 can be
efficiently subjected to regeneration treatment even in a case
where the flow rate in the first liquid supply channel 71 and the
second liquid supply channel 72 is slow.
SEVENTH EMBODIMENT
[0179] The bottom face of the treatment solution regeneration bath
2 may be inclined. When light is radiated to the oxalate treatment
solution 4, as described above, insoluble iron (II) oxalate is
formed. The iron (II) oxalate forms precipitate and settles inside
the treatment solution regeneration bath 2. If the bottom face of
the treatment solution regeneration bath 2 is inclined, the
precipitate may accumulate at a lower part of the inclined bottom
face. In this case, removal of the precipitate is facilitated.
[0180] FIG. 10 to FIG. 12 are schematic diagrams illustrating
examples of the treatment solution regeneration bath 2 in which the
bottom face is inclined.
[0181] Referring to FIG. 10, a bottom face 21 of the treatment
solution regeneration bath 2 inclines linearly downward toward the
center from both ends. In this case, the precipitate accumulates at
the center portion of the treatment solution regeneration bath
2.
[0182] An inclination of the bottom face 21 of the treatment
solution regeneration bath 2 is not limited to the example
illustrated in FIG. 10. The bottom face 21 of the treatment
solution regeneration bath 2, for example, may be inclined linearly
downward from one end towards the other end as illustrated in FIG.
11. The direction in which the bottom face 21 inclines may also be
the opposite direction to the direction illustrated in FIG. 11. The
bottom face 21 of the treatment solution regeneration bath 2 may be
inclined linearly downward from the center toward both ends so that
the center is a convex shape. The bottom face 21 of the treatment
solution regeneration bath 2 may, for example, inline in a curved
manner as illustrated in FIG. 12 without inclining linearly.
EIGHTH EMBODIMENT
[0183] The treatment solution regeneration bath 2 may be
partitioned into a light irradiation chamber and a sedimentation
chamber by a partition member. FIG. 13 is a schematic diagram of
the chemical treatment solution regeneration apparatus 1 according
to another embodiment that is different from FIG. 3 to FIG. 12.
Referring to FIG. 13, the treatment solution regeneration bath 2 is
partitioned into a light irradiation chamber 23 and a sedimentation
chamber 24 by a partition member 22. The partition member 22 has an
opening portion 220 which connects the light irradiation chamber 23
and the sedimentation chamber 24. The one or more light source
members 31 are disposed in the light irradiation chamber 23.
[0184] When the treatment solution regeneration bath 2 is
partitioned into the light irradiation chamber 23 and the
sedimentation chamber 24, light irradiation and the removal of
precipitate can be performed in separate compartments. In this
case, removal of precipitate can be performed more efficiently.
[0185] The size, shape and position of the partition member 22 are
not particularly limited. The partition member 22 may be a
plate-shaped member that extends downward from the top face of the
treatment solution regeneration bath 2. Further, the direction of
the partition member 22 may be the vertical direction or may be a
direction that is inclined with respect to the vertical
direction.
[0186] The opening portion 220 that connects the light irradiation
chamber 23 and the sedimentation chamber 24 is preferably provided
at the lower end of the partition member 22. The opening portion
220 may be provided only at the lower end of the partition member
22, or may be provided both at the lower end of the partition
member 22 and at a position other than the lower end of the
partition member 22. The size, number and position of the opening
portion 220 can be appropriately adjusted within a range in which a
desired flow rate of the oxalate treatment solution 4 is obtained
and a range in which precipitate does not block up the opening
portion 220 and obstruct the flow of the oxalate treatment solution
4.
NINTH EMBODIMENT
[0187] Preferably, the bottom face of the light irradiation chamber
23 becomes lower from the light irradiation chamber 23 toward the
sedimentation chamber 24. FIG. 14 is a schematic diagram of the
chemical treatment solution regeneration apparatus 1 according to
another embodiment that is different from FIG. 3 to FIG. 13. In
comparison to the chemical treatment solution regeneration
apparatus 1 illustrated in FIG. 13, the chemical treatment solution
regeneration apparatus 1 illustrated in FIG. 14 further includes
the under-regeneration-treatment-solution circulation channel 73. A
bottom face 230 of the light irradiation chamber 23 of the
treatment solution regeneration bath 2 of the chemical treatment
solution regeneration apparatus 1 illustrated in FIG. 14 is
inclined linearly downward from the light irradiation chamber 23
toward the sedimentation chamber 24.
[0188] In a case where the bottom face 230 of the light irradiation
chamber 23 becomes lower towards the sedimentation chamber 24 from
the light irradiation chamber 23, after precipitate that is formed
in the light irradiation chamber 23 deposits on the bottom face 230
of the light irradiation chamber 23, the precipitate moves under
its own weight toward the sedimentation chamber 24. The precipitate
passes through the opening portion 220 of the partition member 22
and accumulates in the sedimentation chamber 24. Therefore, removal
of precipitate can be performed more efficiently.
[0189] In FIG. 14, a bottom face 240 of the sedimentation chamber
24 is also inclined. By this means, the precipitate that moved into
the sedimentation chamber 24 moves under its own weight in
accordance with the inclination of the bottom face 240 of the
sedimentation chamber 24 and accumulates at a lower place. In this
case, the removal of precipitate is further facilitated. However,
the bottom face 240 of the sedimentation chamber 24 need not be
inclined.
TENTH EMBODIMENT
[0190] Preferably, the treatment solution regeneration bath 2 also
includes a current direction changing member. The current direction
changing member is disposed so as to be immersible in the oxalate
treatment solution 4 in the treatment solution regeneration bath 2,
and changes the direction of the flow of the oxalate treatment
solution 4 in the treatment solution regeneration bath 2.
[0191] FIG. 15 is a plan view of the treatment solution
regeneration bath 2, that illustrates the arrangement of current
direction changing members 25. The arrows in FIG. 15 indicate the
direction which the oxalate treatment solution 4 flows. Referring
to FIG. 15, the treatment solution regeneration bath 2 includes a
current direction changing member 25. When the treatment solution
regeneration bath 2 includes the current direction changing member
25, the directions of flows of the oxalate treatment solution 4 in
the treatment solution regeneration bath 2 are not uniformly
aligned in a fixed direction, and a turbulent flow can easily be
generated. When a turbulent flow is generated, the amount of
oxalate treatment solution 4 to be irradiated with light increases.
Therefore, the oxalate treatment solution 4 can be subjected to
regeneration treatment more efficiently.
[0192] The number, shape and size of the current direction changing
member 25 are not particularly limited as long as the current
direction changing member 25 can change the direction of the flow
of the oxalate treatment solution 4. The number of current
direction changing members 25 that are provided may be one, may be
two, or may be three or more as illustrated in FIG. 15. The shape
of the current direction changing member 25 may be a plate shape,
may be a bar shape, may be spherical, may be a box shape, or may be
tubular. For example, in a case where the shape of the current
direction changing member 25 is a plate shape, the current
direction changing member 25 may be curved or need not be
curved.
[0193] The arrangement of the current direction changing member 25
can be appropriately adjusted within a range in which the current
direction changing member 25 do not completely hold back the flow
of the oxalate treatment solution 4. Preferably, the current
direction changing member 25 is arranged between a plurality of the
light source members 31 as illustrated in FIG. 15. In this case, a
greater amount of the oxalate treatment solution 4 passes the
vicinity of the light source members 31. Therefore, the amount of
the oxalate treatment solution 4 to be irradiated with light
increases. The current direction changing members 25 may be
arranged such that a plurality of the plate-shaped current
direction changing members 25 are disposed with regularity as
illustrated, for example, in FIG. 16, or may be disposed
irregularly.
ELEVENTH EMBODIMENT
[0194] The chemical treatment solution regeneration apparatus 1 may
have a combination of the features of the foregoing embodiments.
FIG. 17 is a schematic diagram of the chemical treatment solution
regeneration apparatus 1 according to another embodiment that is
different from FIG. 3 to FIG. 16. Referring to FIG. 17, the
chemical treatment solution regeneration apparatus 1 includes the
treatment solution regeneration bath 2, the light radiation
apparatus 3, the first chemical treatment bath 51 and the second
chemical treatment bath 52, and causes the oxalate treatment
solution 4 as a whole to circulate between the first chemical
treatment bath 51 and second chemical treatment bath 52 and the
treatment solution regeneration bath 2, and also causes the oxalate
treatment solution 4 to circulate inside the treatment solution
regeneration bath 2.
[0195] The chemical treatment solution regeneration apparatus 1
includes the treatment solution regeneration bath 2, the first
chemical treatment bath 51 and second chemical treatment bath 52,
the light radiation apparatus 3 and the flow mechanism 7. The
treatment solution regeneration bath 2 is partitioned into the
light irradiation chamber 23 and the sedimentation chamber 24 by
the partition member 22. The bottom face 230 of the light
irradiation chamber 23 and the bottom face 240 of the sedimentation
chamber 24 both incline so as to become lower toward downstream
from upstream of the flow of the oxalate treatment solution 4. The
light source member 31 of the light radiation apparatus 3 is
disposed so as to be immersible in the oxalate treatment solution 4
in the light irradiation chamber 23.
[0196] The flow mechanism 7 includes the first liquid supply
channel 71, the second liquid supply channel 72 and the
under-regeneration-treatment-solution circulation channel 73. The
first liquid supply channel 71 conveys the oxalate treatment
solution 4 in the treatment solution regeneration bath 2 to the
first chemical treatment bath 51 and the second chemical treatment
bath 52. The chemical treatment bath 5 side of the first liquid
supply channel main body 710 of the first liquid supply channel 71
branches in two, and the first chemical-treatment-bath-side
discharge port 714 and the second chemical-treatment-bath-side
discharge port 715 are formed at the two end portions of the first
liquid supply channel main body 710, respectively. The second
liquid supply channel 72 conveys the oxalate treatment solution 4
in the first chemical treatment bath 51 and the second chemical
treatment bath 52 to the treatment solution regeneration bath 2.
The chemical treatment bath 5 side of the second liquid supply
channel main body 720 of the second liquid supply channel 72
branches in two, and the first chemical-treatment-bath-side inflow
port 724 and the second chemical-treatment-bath-side inflow port
725 are formed at the two end portions of the second liquid supply
channel main body 720, respectively. The flow mechanism 7 also
includes the discharge port switching mechanism 716 and the inflow
port switching mechanism 726. By this means, an adjustment can be
made regarding whether to cause the oxalate treatment solution 4 in
the first chemical treatment bath 51 and/or the oxalate treatment
solution 4 in the second chemical treatment bath 52 to
circulate.
[0197] The under-regeneration-treatment-solution circulation
channel 73 causes the oxalate treatment solution 4 in the treatment
solution regeneration bath 2 to circulate. By this means, the
amount of the oxalate treatment solution 4 to be irradiated with
light can be increased, and the oxalate treatment solution 4 is
efficiently regenerated. In FIG. 17, the
under-regeneration-treatment-solution circulation channel 73
conveys the oxalate treatment solution 4 in the sedimentation
chamber 24 to the light irradiation chamber 23.
[0198] After the oxalate treatment solution 4 undergoes the
treatment solution regeneration step, the oxalate treatment
solution 4 is transported to the chemical treatment bath 5. In the
chemical treatment bath 5, chemical treatment is performed once
more using the oxalate treatment solution 4 after the treatment
solution regeneration step. The oxalate treatment solution 4 in the
chemical treatment bath 5 after the oxalate treatment solution 4
was transported to the chemical treatment bath 5 may be the oxalate
treatment solution 4 that is after undergoing the treatment
solution regeneration step, or may be a mixture of unused oxalate
treatment solution 4 and the oxalate treatment solution 4 that is
after undergoing the treatment solution regeneration step. That is,
it may be the oxalate treatment solution 4 which includes the
oxalate treatment solution 4 after the treatment solution
regeneration step.
OTHER EMBODIMENTS
[0199] The method for producing a chemically treated alloy material
of the present disclosure is not limited to the aforementioned
methods for producing a chemically treated alloy material.
Development examples are described hereunder.
[Position of Light Source Member]
[0200] The light source member 31 is preferably arranged inside the
treatment solution regeneration bath 2 in a manner in which light
source member 31 is immersible in the oxalate treatment solution 4.
The arrangement of the light source member 31 can be appropriately
changed.
[0201] FIG. 18 is a schematic diagram illustrating an example of
the arrangement of the light source member 31. As illustrated in
FIG. 18, the light source member 31 may be disposed in the vicinity
of the outside of the treatment solution regeneration bath 2. For
example, the light source member 31 may be disposed above the
treatment solution regeneration bath 2. In this case, the top face
of the treatment solution regeneration bath 2 is open, or a top
plate composed of a member having translucency is mounted at a
location facing the light source member 31. In a case where the
light source member 31 is disposed above the treatment solution
regeneration bath 2, preferably the light source member 31 is
disposed as close as possible to the liquid surface of the
treatment solution in order to suppress attenuation of the light
when the light propagates through the atmosphere.
[0202] Alternatively, a member having translucency may be used at
one part of a side face of the treatment solution regeneration bath
2, and the light source member 31 may be disposed at the side of
the treatment solution regeneration bath 2. FIG. 19 is a schematic
diagram illustrating an example of the arrangement of the light
source members 31 that is different from FIG. 18. For example, as
illustrated in FIG. 19, a plurality of the light source members 31
having a cylindrical shape may be disposed so that the axial
directions of the light source members 31 are aligned along a long
side of the side faces on the outer side of the treatment solution
regeneration bath 2.
[0203] In a case where the light source member 31 is disposed above
the treatment solution regeneration bath 2, preferably the light
source member 31 is disposed so as to be located within a range of
200 mm from the liquid surface of the treatment solution that is
contained in the treatment solution regeneration bath 2, more
preferably within a range of 100 mm, and further preferably within
a range of 50 mm. Further, an a case where the light source member
31 is disposed at the side of the treatment solution regeneration
bath 2, preferably the light source member 31 is disposed so as to
be located within a range of 100 mm from the surface of a member
having translucency of a side face of the treatment solution
regeneration bath 2, and more preferably is mounted to the surface
of the member having translucency.
[0204] FIG. 20 is a schematic diagram illustrating an example of
the arrangement of the light source members 31 that is different
from FIG. 18 and FIG. 19. Referring to FIG. 20, the light source
members 31 having a cylindrical shape may be disposed so that each
entire light source member 31 is disposed inside the treatment
solution regeneration bath 2 in a manner in which the axial
direction of the light source member 31 is aligned with the width
direction of the treatment solution regeneration bath 2.
[0205] FIG. 21 is a schematic diagram illustrating an example of
the arrangement of the light source members 31 that is different
from FIG. 18 to FIG. 20. FIG. 21 is a view in which the treatment
solution regeneration bath 2 is seen from above. The arrows in FIG.
21 indicate the direction of the flow of the oxalate treatment
solution 4. In a case in which a plurality of the light source
members 31 are provided inside the treatment solution regeneration
bath and which is a case where the oxalate treatment solution 4
flows, as illustrated in FIG. 21, the light source members 31 may
be arranged in series in a direction that is orthogonal to the
direction of the flow of the oxalate treatment solution 4, or may
be arranged randomly with respect to the direction of the flow of
the oxalate treatment solution 4.
[Shape of Treatment Solution Regeneration Bath]
[0206] The shape of the treatment solution regeneration bath 2 is
not particularly limited as long as the shape enables light to be
radiated to the oxalate treatment solution 4, and the shape can be
altered as appropriate.
[0207] FIG. 22 is a schematic diagram illustrating an example of
the shape of the treatment solution regeneration bath 2. The arrows
in FIG. 22 indicate the direction of the flow of the oxalate
treatment solution 4 in the treatment solution regeneration bath 2.
Referring to FIG. 22, in the treatment solution regeneration bath
2, one side face may be a box shape that is formed in a stepped
shape. In this case, for example, a plurality of the light source
members 31 having a cylindrical shape may be disposed so that the
axial direction thereof is along the width direction of the
treatment solution regeneration bath 2, with one light source
member 31 being disposed in each step of the stepped side face. In
this case, the area that can be irradiated with light from the
light source member 31 increases. As a result, the oxalate
treatment solution 4 can be subjected to regeneration treatment
more efficiently.
[0208] FIG. 23 is a schematic diagram illustrating an example of
the shape of the treatment solution regeneration bath 2 that is
different from FIG. 22. The treatment solution regeneration bath 2
may be one part of a liquid supply channel. The treatment solution
regeneration bath 2 illustrated in FIG. 23 is one part of the
liquid supply channel main body 720. In FIG. 23, the light source
members 31 are disposed in the vicinity of the outer side of the
treatment solution regeneration bath 2. In this case, at least a
face of the treatment solution regeneration bath 2 which faces the
light source member 31 is composed of a member having translucency.
The light source members 31 may be disposed above and below the
treatment solution regeneration bath 2 as illustrated in FIG. 23,
or may be disposed so as to surround the outside of the treatment
solution regeneration bath 2 that is a liquid supply channel.
Although in the example illustrated in FIG. 23 a sedimentation bath
8 is disposed downstream of the treatment solution regeneration
bath 2, the sedimentation bath 8 need not be provided.
[0209] FIG. 24 is a schematic diagram illustrating an example of
the shape of the treatment solution regeneration bath 2 that is
different from FIG. 22 and FIG. 23. Referring to FIG. 24, the
treatment solution regeneration bath 2 may be, for example, a tower
shape. Specifically, the treatment solution regeneration bath 2 is
a rectangular parallelepiped shape that has long sides extending in
the vertical direction, and the light source members 31 are
disposed inside the treatment solution regeneration bath 2. The
light source member 31 is cylindrical, and a plurality of the light
source members 31 are disposed so that the longitudinal direction
thereof is perpendicular to the direction of the flow of the
oxalate treatment solution 4 in the treatment solution regeneration
bath 2. The oxalate treatment solution 4 flows into the treatment
solution regeneration bath 2 from a lower portion of the treatment
solution regeneration bath 2, and flows from the lower portion
toward the upper portion of the treatment solution regeneration
bath 2. The oxalate treatment solution 4 that is discharged from
the upper portion of the treatment solution regeneration bath 2
passes through a liquid supply channel 82, and is discharged into
the sedimentation bath 8 provided ahead of the liquid supply
channel 82. The lower portion of the sedimentation bath 8 is
openable, and a removal apparatus 81 for recovering precipitate is
disposed below the sedimentation bath 8. A side face of the
sedimentation bath 8 has a hole, and the oxalate treatment solution
4 in the sedimentation bath 8 is discharged from the hole in the
side face of the sedimentation bath 8.
[0210] FIG. 25 is a schematic diagram illustrating an example of
the shape of the treatment solution regeneration bath 2 that is
different from FIG. 22 to FIG. 24. Referring to FIG. 25, the
treatment solution regeneration bath 2 may be a tower shape in
which the oxalate treatment solution 4 flows from the upper portion
toward the lower portion. In this case, the treatment solution
regeneration bath 2 has, in the upper portion, an opening portion
through which the oxalate treatment solution 4 flows into the
treatment solution regeneration bath 2, and has an opening portion
through which the oxalate treatment solution 4 is discharged in the
lower portion. A driving source 83 for feeding liquid may be
disposed on the liquid supply channel 82 between the treatment
solution regeneration bath 2 and the sedimentation bath 8. The
remaining configuration of the example in FIG. 25 is the same as
the configuration of the example in FIG. 24.
[Other Arrangement Examples]
[0211] In a case where the chemical treatment solution regeneration
apparatus 1 includes the chemical treatment bath 5, the arrangement
of the treatment solution regeneration bath 2 and the chemical
treatment bath 5 can be changed as appropriate.
[0212] FIG. 26 is a schematic diagram of the chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different from FIG. 3 to FIG. 25. Referring to FIG. 26, the
chemical treatment solution regeneration apparatus 1 includes the
treatment solution regeneration bath 2 and the chemical treatment
bath 5. The treatment solution regeneration bath 2 and the chemical
treatment bath 5 are not connected. The light source member 31 is
disposed inside the treatment solution regeneration bath 2.
[0213] In the case of using the chemical treatment solution
regeneration apparatus 1 illustrated in FIG. 26, the oxalate
treatment solution 4 that underwent regeneration treatment is
returned to the chemical treatment bath 5 by transportation means,
and is again utilized for chemical treatment. The term
"transportation means" refers to, for example, transportation by a
container. In this case, the oxalate treatment solution 4 in the
chemical treatment bath 5 is the oxalate treatment solution 4 after
undergoing the treatment solution regeneration step or is a mixture
of unused oxalate treatment solution 4 and the oxalate treatment
solution 4 after undergoing the treatment solution regeneration
step.
[0214] FIG. 27 is a schematic diagram of the chemical treatment
solution regeneration apparatus 1 according to another embodiment
that is different from FIG. 3 to FIG. 26. Referring to FIG. 27, the
oxalate treatment solution 4 that underwent regeneration treatment
in the treatment solution regeneration bath 2 need not necessarily
be returned to the same chemical treatment bath 5. In the
embodiment illustrated in FIG. 27, after the oxalate treatment
solution 4 that was in the chemical treatment bath 5 undergoes
regeneration treatment inside the treatment solution regeneration
bath 2, the oxalate treatment solution 4 is discharged into a
chemical treatment bath 53 that is different from the chemical
treatment bath 5. For example, the oxalate treatment solution 4 in
the chemical treatment bath 53 may be returned to the chemical
treatment bath 5 by means of an unshown liquid supply channel. In
this case, the embodiment is of a form in which the chemical
treatment solution is regenerated after being used in both of the
chemical treatment bath 53 and the chemical treatment bath 5. By
this means, even in a case where chemical treatment is performed
repeatedly in the chemical treatment bath 5 and the chemical
treatment bath 53, a decrease in the chemical treatability is
suppressed. Alternatively, unused oxalate treatment solution 4 may
be supplied to the chemical treatment bath 5, and the oxalate
treatment solution 4 that is in the chemical treatment bath 53 may
be discarded after performing chemical treatment. In this case,
even when using the oxalate treatment solution 4 after the oxalate
treatment solution 4 was used for chemical treatment inside the
chemical treatment bath 5, a decrease in the chemical treatability
within the chemical treatment bath 53 is suppressed.
EXAMPLE
[0215] As an example, a test was performed with respect to
decreasing iron ions by light irradiation. An oxalate treatment
solution having the following composition was prepared. [0216]
Felbond 3819A (produced by Nihon Parkerizing Co., Ltd.) [0217]
Oxalic acid: 92% [0218] Sodium bifluoride: 1 to 8% [0219] Felbond
3819B (produced by Nihon Parkerizing Co., Ltd.) [0220] Sodium
nitrate: 40 to 50% [0221] In the test, an oxalate treatment
solution in which Felbond 3819A and Felbond 3819B were mixed at a
mass ratio of Felbond 3819A: Felbond 3819B =4:1 was used.
[0222] The prepared oxalate treatment solution was used to perform
a chemical treatment on a duplex stainless steel material (ASTM UNS
539274) containing 25% of Cr, 7% of Ni, 3% of Mo, and 2% of W. The
chemical treatment conditions were treatment at 90.degree. C. for
20 minutes.
[Light Irradiation Test]
[0223] Ultraviolet light was radiated to the oxalate treatment
solution after the chemical treatment, and the iron ion content of
the oxalate treatment solution before and after the ultraviolet
light irradiation was measured. The ultraviolet light radiation
conditions were a wavelength of 365 nm, and an radiation time of
six minutes. The oxalate treatment solution before ultraviolet
irradiation and the oxalate treatment solution after ultraviolet
irradiation were each analyzed using an emission spectrophotometer
(ICP-OES) PS7800 manufactured by Hitachi High-Technologies
Corporation. The measurement results are shown in FIG. 1.
[Chemical Treatment Test]
[0224] A chemical treatment test was performed using an unused
oxalate treatment solution, a used oxalate treatment solution, and
a used oxalate treatment solution after ultraviolet irradiation.
The alloy material subjected to the chemical treatment was an alloy
material with a Cr content of 25%. The conditions of the chemical
treatment were treatment at a temperature of 90.degree. C. for 20
minutes. The potential on the alloy material surface during the
chemical treatment was measured using a potentiostat in a manner in
which a saturated calomel electrode was adopted as a reference
electrode. The results are shown in FIG. 2.
[Test Results]
[0225] Referring to FIG. 1, when the used oxalate treatment
solution was subjected to ultraviolet irradiation, the iron ion
content decreased. Further, referring to FIG. 2, by subjecting the
used oxalate treatment solution to ultraviolet irradiation
("Regenerated Treatment Solution" in FIG. 2), the chemical
treatability were restored to the same level as the chemical
treatability of the unused oxalate treatment solution ("Unused
Solution" in FIG. 2).
[0226] Embodiments of the present invention have been described
above. However, the foregoing embodiments are merely examples for
implementing the present invention. Accordingly, the present
invention is not limited to the above embodiments, and the above
embodiments can be appropriately modified within a range which does
not deviate from the gist of the present invention.
REFERENCE SIGNS LIST
[0227] 1 Chemical Treatment Solution Regeneration Apparatus [0228]
2 Treatment Solution Regeneration Bath [0229] 3 Light radiation
apparatus [0230] 4 Oxalate Treatment Solution [0231] 6 Alloy
Material [0232] 31 Light Source Member
* * * * *